This guide covers the rules on S106 spending, the common questions monitoring officers face, and how to handle situations where the intended purpose no longer applies.

This covers England only. This is general guidance, not legal advice. Always refer to the specific terms of each S106 agreement.

The Basic Rule: Purpose-Restricted Spending

Section 106 of the Town and Country Planning Act 1990 allows obligations that require sums to be paid to the authority "on a specified date or dates or periodically." The specific purposes are defined in the agreement — not by the council after receipt.

Typical purpose restrictions include:

The wording varies by agreement. Some are tightly defined ("towards the extension of Elm Road Primary School"). Others are broader ("towards primary education provision within 3 miles of the site"). The tighter the wording, the less flexibility the council has.

What You Cannot Do

Redirect to a Different Purpose

An education contribution cannot fund a highway improvement, even if the highway serves the school. The purpose in the agreement controls.

If no eligible education project exists within the defined area and the spend-by deadline is approaching, the options are:

1. Identify an eligible project — even a small one (equipment, temporary classrooms, capacity improvements)
2. Negotiate a deed of variation with the developer to widen the purpose or area (requires developer consent)
3. Accept the clawback — return the money to the developer before the deadline expires

Option 3 is painful but legally clean. Spending money outside the purpose restriction risks a legal challenge from the developer and an audit finding.

Spend Outside the Defined Area

If the agreement says "within 2 miles of the Site," a school expansion 3 miles away doesn't qualify — even if it serves children from the development.

Use S106 to Fund Infrastructure Already on the Council's Infrastructure List

If your council charges CIL and your Infrastructure List identifies education as a CIL-funded category, you generally cannot also spend S106 education contributions on the same strategic infrastructure (to avoid double-counting). Site-specific S106 contributions for purposes not covered by CIL remain valid. See S106 vs CIL: A Planning Officer's Guide for how the two systems interact.

Accumulate Without Spending

Holding S106 money indefinitely is not a strategy — it's a risk. Spend-by deadlines exist in most agreements, and the Home Builders Federation actively monitors unspent balances across councils. Even without a deadline, accumulating large unspent balances invites scrutiny from auditors, councillors, and the community.

Common Spending Questions

"Can we pool multiple S106 contributions on one project?"

Yes. Since the 2019 CIL regulation amendments removed the pooling restriction (which previously limited S106 contributions to no more than 5 agreements per infrastructure project), you can now combine contributions from multiple agreements — provided each contribution's purpose restriction allows it.

This is important for large infrastructure projects. A £500,000 school extension might be funded by education contributions from 8 different S106 agreements, each for £50,000–£80,000.

Monitoring requirement: Record which contributions are funding which project, and track spend against each contribution separately. The spend-by deadlines may differ — contribution A might have 3 years left while contribution B has 7 years.

"Can we spend S106 money on staff costs?"

Generally, no — unless the agreement specifically allows it. S106 contributions are for infrastructure, not operational costs. An education contribution funds school places (capital), not teacher salaries (revenue).

However, some agreements include monitoring fee clauses, which are separate from infrastructure contributions and can fund the monitoring officer's time.

"The project we allocated the money to has been cancelled. What now?"

Reallocate to another eligible project within the same purpose and area. Document the change of allocation, including the reason the original project was cancelled and why the new project qualifies.

If no alternative project exists, the contribution is at risk of clawback when the spend-by deadline arrives. Start looking for eligible projects immediately — don't wait until the deadline is imminent.

"Can we spend accrued interest?"

Interest accrued on S106 contributions held in council accounts is generally treated as part of the contribution and must be spent on the same purpose. Some agreements specifically address interest treatment — check the wording.

The IFS Reporting Connection

Your annual Infrastructure Funding Statement requires you to report S106 money received, spent, and retained — broken down by infrastructure type. If your spending records don't track purpose categories consistently, the IFS becomes a manual reconciliation exercise.

Standardise your purpose categories across all agreements and align them with IFS reporting categories. When a new agreement arrives, assign each obligation to a standard category in your register. This saves hours at reporting time.

For a step-by-step IFS process, see How to Produce Your Infrastructure Funding Statement in Half the Time.

Sources

• Town and Country Planning Act 1990, Section 106
• Community Infrastructure Levy Regulations 2010
• GOV.UK — Planning Obligations Guidance
• PAS — Infrastructure Funding Statements
• Home Builders Federation — S106 Unspent Contributions Report

Here's how the timelines actually work and what planning officers need to track.

This covers England only. This is general guidance, not legal advice.

The Short Answer

An S106 obligation lasts until it's discharged — meaning the obligation has been fully performed. For financial contributions, that means the money has been paid, received, and (from the council's perspective) spent. For in-kind obligations, it means the infrastructure has been delivered and accepted.

There is no automatic expiry. An obligation that hasn't been triggered because the development hasn't commenced can sit dormant indefinitely.

Key Timelines in S106 Agreements

Planning Permission Duration

The underlying planning permission typically has a 3-year commencement condition: development must begin within 3 years of the permission date. If the developer doesn't commence, the permission lapses — and with it, the S106 agreement may become unenforceable, as the obligations are tied to the planning permission. The position can depend on the agreement's wording and whether any development has commenced, so seek legal advice before assuming an obligation has lapsed.

However, if the developer commences within 3 years (even by digging a trench), the permission is live and the S106 obligations remain binding for the life of the development.

Spend-By Deadlines

Financial contributions carry spend-by deadlines defined in each agreement — typically 5 to 10 years from the date the council receives the payment. These are the most critical timelines for monitoring officers. See S106 Spend Deadlines: What Happens When Developer Money Expires for the full process.

The 5-Year Modification Window

Section 106A of the Town and Country Planning Act 1990 allows any person bound by a planning obligation to apply to the LPA to have it modified or discharged after 5 years from the date the obligation was entered into.

The LPA can:

• Approve the modification or discharge
• Modify the terms (different from what was requested)
• Refuse to modify or discharge

If the LPA refuses, the applicant can appeal to the Planning Inspectorate.

This 5-year window is relevant because developers occasionally use it to reduce or remove obligations that were negotiated years earlier — particularly where market conditions have changed or the development has shifted.

What monitoring officers should watch for: Applications to modify obligations on agreements that are 5+ years old. These may affect financial contributions you're expecting to receive or in-kind obligations you're tracking.

Phased Development Timelines

Large developments are delivered in phases over 10–20 years. Each phase may trigger different S106 obligations:

• Phase 1 (years 1–3): Commencement triggers, initial infrastructure contributions
• Phase 2 (years 4–7): Occupation-based triggers, affordable housing delivery
• Phase 3 (years 8–12): Remaining triggers, final contributions
• Ongoing: Maintenance obligations, monitoring fees

This means your S106 register needs to track the development phase alongside each obligation's status. An agreement signed in 2020 may have Phase 3 triggers that won't fire until 2032.

What This Means for Monitoring

Long-Running Agreements Need Active Monitoring

An agreement signed in 2015 with a phased development is still generating obligations in 2026. If your monitoring relies on institutional memory rather than structured records, obligations from older agreements are the ones most likely to fall through the cracks — especially if the officer who set up the monitoring has moved on.

Practical steps:

• Review all agreements older than 5 years annually
• Check whether triggers have been reached but not recorded
• Verify that financial contribution records are complete (receipt dates, indexation, allocation)
• Confirm whether the development is still progressing or has stalled

Dormant Agreements

Some S106 agreements are attached to permissions that were never implemented. The permission hasn't lapsed (commencement occurred) but the development has stalled. The obligations are technically still binding.

These dormant agreements shouldn't consume active monitoring time, but they should be flagged in your register. If the development restarts (which can happen years later when the site is sold), the obligations reactivate.

Succession in Title

S106 obligations run with the land, not with the developer. If the site is sold to a new owner, they inherit the obligations. This matters for monitoring because:

• Your developer contact may change without notification
• The new owner may not be aware of the obligations
• Invoicing a developer who no longer owns the site creates delays

When you become aware of a site sale, update your register with the new owner details and re-establish contact for trigger monitoring and invoicing.

Common Questions from Officers

Can we enforce an obligation from a 15-year-old agreement? Potentially, yes — if the obligation hasn't been discharged and the trigger has been reached. S106 obligations run with the land and are not subject to the standard six-year limitation period for simple contracts. However, enforcing older obligations can involve practical difficulties (poor records, changes in site ownership, unclear trigger evidence), so seek legal advice before pursuing enforcement on historic agreements.

What if the developer has dissolved? The obligation runs with the land. Identify the current landowner and enforce against them.

Can we discharge a completed obligation? You can confirm in writing that an obligation has been satisfied. Some councils maintain a discharge log alongside their S106 register. This is good practice — it prevents confusion about whether an obligation is still active.

What happens to an agreement if the permission is superseded by a new application? The original S106 agreement remains unless it's specifically discharged or replaced by a new agreement attached to the new permission. Check whether the new permission's S106 supersedes or supplements the original.

For the complete monitoring process, see The Complete Guide to S106 Monitoring for Planning Officers.

Sources

• Town and Country Planning Act 1990, Section 106
• Town and Country Planning Act 1990, Section 106A (Modification and Discharge)
• GOV.UK — Planning Obligations Guidance

This guide covers the practical mechanics of S106 financial tracking, with a focus on the calculations and processes that prevent money from being lost, miscounted, or returned to developers.

This covers England only. This is general guidance, not legal advice.

The Financial Tracking Record

Each financial contribution needs these fields tracked:

This is too many fields for a single spreadsheet row — which is exactly why spreadsheet-based tracking breaks down at scale.

Indexation: The Calculation Most Councils Get Wrong

Most S106 financial contributions are index-linked. The agreement states a base amount and specifies an index (usually BCIS All-in Tender Price Index, sometimes RPI or CPI). The amount the developer owes is the base amount adjusted by the index movement from the base date to the calculation date.

The calculation:

Indexed Amount = Base Amount × (Index at Calculation Date ÷ Index at Base Date)

Example:

• Base amount: £150,000
• Index basis: BCIS All-in Tender Price Index
• Base date: Q1 2021 (index value: 388)
• Calculation date: Q1 2026 (index value: 461)
• Indexed amount: £150,000 × (461 ÷ 388) = £178,222

Note: the index values above are illustrative. Actual BCIS figures should be obtained from RICS at the point of calculation.

If you invoice £150,000 instead of £178,222, you've left £28,222 on the table for that single obligation. Across a portfolio of 100+ financial obligations, systematic under-indexation can cost a council hundreds of thousands.

Common indexation mistakes:

• Using the wrong index (the agreement says BCIS, the officer uses RPI)
• Using the wrong base date (using the agreement date when the index clause specifies a different quarter)
• Not indexing at all (invoicing the base amount verbatim from the agreement)
• Using an outdated index value (the index is published quarterly — check you're using the current figure)

BCIS index values are published by the Royal Institution of Chartered Surveyors (RICS) and require a subscription. If your council doesn't have BCIS access, check whether the index is available through your quantity surveying or property team.

Receipts: The Point Where Everything Gets Recorded

When finance confirms a developer payment:

1. Match to obligation. Identify which agreement and which obligation the payment satisfies. Developers sometimes pay a lump sum covering multiple obligations — split and allocate each portion.

2. Record the receipt date. This is the date the money hit the council's bank account, not the date the invoice was issued. The spend-by deadline is calculated from this date.

3. Check the amount. Does it match the indexed invoice? If less, record the shortfall and follow up with the developer. If more (overpayment), clarify with the developer and record accordingly.

4. Calculate the spend-by deadline. Receipt date + spend-by period from the agreement. If the agreement says "5 years from receipt," and the receipt date is 15 March 2026, the deadline is 15 March 2031.

5. Set alerts. At minimum: 18 months, 12 months, 6 months, and 3 months before deadline.

6. Notify the service area. The team responsible for spending the contribution (education, highways, parks) needs to know money has arrived and when it needs to be spent.

Allocation: Not the Same as Spend

Allocating a contribution to a project is an administrative decision. Spending it is a financial transaction. They are different events with different dates, and both need tracking.

Common confusion: A council allocates £200,000 of education contributions to a school expansion. The project is scheduled for next year. The monitoring officer marks the contribution as "allocated" and moves on. Two years later, the project is delayed. The contribution is still allocated-but-unspent, and the deadline is now 18 months away.

Track allocation and spend separately:

The highest-risk category is "received, unallocated" — money sitting in a holding account with no plan. The second-highest is "allocated, unspent" where the project timeline doesn't fit within the spend-by window.

Reconciliation with Finance

Your S106 monitoring records and the council's finance system will diverge. This is normal but needs regular reconciliation:

Why they diverge:

• Finance records a payment as a single transaction; S106 monitoring needs it split across obligations
• S106 records obligations by agreement reference; finance may use a different coding scheme
• Indexation adjustments appear in S106 records but not in finance (the invoice was for the indexed amount, but finance records the receipt)
• Transfers between S106 holding accounts and project budgets may not be reflected in S106 records

Quarterly reconciliation process:

1. Export S106 contribution receipts from your monitoring records
2. Export matching receipts from the finance system
3. Match by amount, date, and developer name
4. Investigate any unmatched entries
5. For each matched entry, confirm the receipt date and amount agree

Do this quarterly, not annually. Annual reconciliation (usually forced by IFS) means 12 months of discrepancies to untangle in December.

Clawback Prevention

The spend-by deadline is the hardest deadline in S106 monitoring. If unspent contributions cross it, the developer has a contractual right to reclaim them — see S106 Spend Deadlines: What Happens When Developer Money Expires for the full implications.

A financial tracking system prevents clawbacks by:

• Recording receipt dates (so deadlines can be calculated)
• Calculating and displaying spend-by deadlines (so they're visible)
• Alerting officers at defined intervals (so deadlines don't arrive silently)
• Tracking allocation and spend status (so at-risk contributions are identified early)
• Generating reports for senior leadership (so escalation happens before the deadline, not after)

For a quick check of your current deadlines, use the S106 Spend Deadline Calculator.

For the broader monitoring framework, see The Complete Guide to S106 Monitoring for Planning Officers.

Sources

• Town and Country Planning Act 1990, Section 106
• Community Infrastructure Levy Regulations 2010
• PAS — Infrastructure Funding Statements
• GOV.UK — Planning Obligations Guidance

This guide traces the full contribution lifecycle and highlights where monitoring effort should focus.

This covers England only. This is general guidance, not legal advice.

The Contribution Lifecycle

Every S106 financial contribution moves through six stages. Your monitoring system needs to track transitions between each one.

Stage 1: Obligation Agreed

The S106 agreement is signed. Each financial obligation is recorded with:

• Purpose (education, highways, open space, healthcare, community facilities)
• Base amount
• Indexation basis and base date (usually BCIS All-in Tender Price Index or RPI)
• Trigger event (commencement, occupation threshold, phase completion)
• Spend-by period (from the clawback clause — typically 5–10 years from receipt)

At this stage, no money changes hands. The obligation exists on paper. Your job is to extract it from the legal agreement and record it as a separate tracked item in your register.

Stage 2: Trigger Activated

A development milestone activates the obligation. How you find out about triggers depends on:

• Commencement notices — developers must notify the LPA before commencing development. Cross-reference with building control records.
• Building control completions — for occupation-based triggers, completion certificates indicate when dwellings are being occupied.
• Developer notifications — some agreements require the developer to notify the council when triggers are reached. Don't rely on this alone.
• Site visits — periodic site visits can verify milestones, particularly for non-residential triggers.

When a trigger fires, record the trigger date and update the obligation status. This is the point where you can invoice the developer.

Stage 3: Invoice Issued

Calculate the indexed amount at the invoice date and issue the demand. The indexed amount will differ from the base amount in the agreement:

Example:

• Base amount: £200,000
• Agreement date (base date): January 2022
• Invoice date: April 2026
• BCIS index change: +18%
• Indexed amount: £236,000

If you invoice the base amount (£200,000), you're under-collecting by £36,000. For a council managing 50+ financial contributions, systematic under-indexation could cost hundreds of thousands across the portfolio.

Record: invoice date, indexed amount, invoice reference, developer contact.

Stage 4: Payment Received

Finance confirms the payment has arrived. This is the critical monitoring point because:

• The spend-by deadline clock starts here. Not at the trigger date, not at the invoice date. At the receipt date. Record it.
• Split receipts need matching. If the developer pays a lump sum covering multiple obligations, split and allocate each portion to the correct obligation.
• The amount may not match the invoice. Developers sometimes dispute the indexation calculation. Record the actual amount received and flag any shortfall.

Calculate the spend-by deadline: receipt date + spend-by period from the agreement. Set alerts at 18, 12, 6, and 3 months before expiry.

Use the S106 Spend Deadline Calculator to calculate deadlines and export them to your calendar.

Stage 5: Allocated to Project

The contribution is earmarked for a specific infrastructure project:

• Education contribution → new classroom block at Elm Road Primary
• Highways contribution → junction improvement at A456/B789
• Open space contribution → playground equipment at Riverside Park

Allocation is a planning/service area decision, not a finance action. Record: project name, service area contact, allocation date, expected spend timeline.

Allocation does not stop the spend-by deadline. The money needs to be spent — not just earmarked. If the project is delayed, the deadline still applies.

Stage 6: Spent and Evidenced

The contribution is disbursed — invoices paid, contracts completed, infrastructure delivered. Record: spend date, amount spent, project reference, evidence (invoices, completion certificates).

If the full contribution is spent, the obligation can be marked as discharged. If partially spent, record the balance and continue tracking the remainder against the spend-by deadline.

Where the Lifecycle Breaks Down

The Gap Between Stages 2 and 3

Triggers fire but nobody invoices. This happens when trigger monitoring relies on the developer to self-report. If the development reaches its 50th occupation and nobody records it, the obligation sits in Stage 1 indefinitely — money owed but never collected.

Fix: Monthly cross-referencing of building control data against your S106 register. This takes 2–3 hours per month and is the single highest-ROI monitoring activity.

The Gap Between Stages 4 and 5

Money is received but never allocated. Contributions sit in a holding account because no service area has claimed them. This is how councils accumulate millions in unspent S106 funds.

Fix: When a contribution is received, notify the relevant service area immediately. Set a 6-month allocation deadline. If unallocated after 6 months, escalate to a senior officer.

The Gap Between Stages 5 and 6

A project is identified but never spends the money. Capital programmes slip. Budget priorities change. The contribution sits allocated-but-unspent while the deadline approaches.

Fix: Track spend status separately from allocation. An allocated contribution with 12 months left on its deadline needs the same urgency as an unallocated one.

Non-Financial Contributions

Not all developer contributions are cash. In-kind obligations follow a parallel lifecycle:

1. Agreed — obligation recorded in the S106 agreement
2. Triggered — development milestone reached
3. Commenced — works started or units under construction
4. Delivered — completed to specification and accepted/adopted
5. Discharged — obligation formally discharged

For in-kind obligations, Stage 4 (delivery verification) requires coordination with the service area that will adopt or accept the infrastructure — highways authority for roads, housing team for affordable units, parks team for open space.

For a complete monitoring setup process, see The Complete Guide to S106 Monitoring for Planning Officers.

Sources

• Town and Country Planning Act 1990, Section 106
• GOV.UK — Planning Obligations Guidance
• PAS — Infrastructure Funding Statements
• Home Builders Federation — S106 Unspent Contributions Report

This guide covers the specific data points planning teams need to record and monitor for S106 affordable housing obligations.

This covers England only. This is general guidance, not legal advice. Affordable housing policy varies by local plan area.

What S106 Affordable Housing Obligations Typically Require

Under the National Planning Policy Framework, major developments (10+ units or sites of 0.5+ hectares) are expected to contribute to affordable housing delivery. The specific percentage and tenure mix are set by your council's local plan, but a typical S106 affordable housing obligation includes:

• Number of units — usually expressed as a percentage of total units (e.g. 30%, 35%, 40%)
• Tenure mix — the split between social rent, affordable rent, shared ownership, First Homes, and any other intermediate products
• Delivery trigger — when affordable units must be built and transferred (e.g. "before occupation of 50% of market dwellings")
• Registered provider — named in the agreement or subject to council approval
• Size mix — number of 1-bed, 2-bed, 3-bed units (to match local housing need)
• Location on site — where affordable units are positioned (to prevent clustering)
• Design standards — affordable units must be indistinguishable from market units
• Mortgagee exemption clause — standard clause allowing a mortgagee in possession to sell market units if the registered provider defaults

The Five Monitoring Data Points

1. Delivery Trigger Status

The delivery trigger is your primary monitoring mechanism. Common trigger wordings:

• "No more than [X]% of the Market Dwellings shall be Occupied until [all / a proportion] of the Affordable Dwellings have been Transferred to the Registered Provider"
• "Prior to the Occupation of the [Nth] Market Dwelling"
• Phase-specific triggers on larger schemes

What to track:

• Trigger milestone (which occupation count or phase completion)
• Current build progress (how many market dwellings are occupied)
• Whether the trigger point has been reached
• Whether the affordable units have been transferred

Common problem: Developers occupy market dwellings past the trigger point before affordable housing is delivered. By the time the planning team notices, it's a breach — and enforcement action is retrospective and slow. Monthly checks of building control completion data against your S106 trigger register catch this early.

2. Tenure Mix Compliance

The agreement specifies the tenure split. The delivered units must match.

What to check:

• Social rent units delivered match the agreement count
• Affordable rent levels are at the agreed percentage of market rent (usually no more than 80%)
• Shared ownership units match the agreed terms
• First Homes are priced at the required discount (minimum 30% below market value, capped at £250,000 outside London)

Common problem: Registered providers may deliver all units as affordable rent rather than the specified mix of social rent and shared ownership. This is commercially rational for the RP but doesn't match the agreement. Check the tenure of completed units against the schedule — don't assume the RP has followed the S106 terms.

3. Size Mix Delivery

The agreement usually specifies a unit size mix to match local housing need:

What to track: Record the size of each delivered unit and compare against the schedule. Developers sometimes substitute larger units for smaller ones (or vice versa) during construction. The housing team should verify the delivered mix against the agreement before accepting the units.

4. Commuted Sums (Off-Site Contributions)

Where on-site affordable housing delivery is not feasible (viability, site constraints, or policy allows), the S106 may require a commuted sum — a financial contribution in lieu of on-site units.

Commuted sums are calculated using a formula specified in the agreement or your council's SPD. The typical basis is the difference between open market value and affordable value of the units that would have been provided.

What to track:

Commuted sums follow the same financial tracking process as any S106 financial contribution — but the amounts are typically large (£100,000+), making deadline management critical. See S106 Spend Deadlines: What Happens When Developer Money Expires for the full deadline management process.

5. Cascade Clauses and Viability Reviews

Many S106 agreements include cascade clauses that reduce the affordable housing obligation if the developer can demonstrate the scheme is unviable at the agreed percentage. These typically work in stages:

1. Full obligation (e.g. 35% affordable housing)
2. First cascade: reduced percentage or altered tenure mix
3. Second cascade: commuted sum in lieu of on-site delivery
4. Final cascade: no affordable housing (rare — usually requires independent viability assessment)

What to track:

• Whether the developer has triggered a viability review
• Independent assessor appointment and terms of reference
• Outcome of the review (accepted / rejected / modified)
• Revised obligation terms (if modified)
• Review period (some agreements allow viability to be re-tested at defined intervals)

Cascade clauses need attention because they can reduce the affordable housing delivery significantly. The planning team should be aware of any viability review before it concludes — not after the developer has already proceeded with a reduced obligation.

Coordinating with Your Housing Team

Affordable housing monitoring crosses team boundaries. The planning team manages the S106 agreement. The housing team manages the relationship with registered providers and monitors delivery against local housing need.

Establish clear responsibilities:

The housing team needs to know the trigger point and the agreed specification before the trigger is reached — not when you ask them for IFS data in November.

For setting up monitoring for new agreements, use the S106 Agreement Checklist Generator — select "Affordable Housing" to get a tailored checklist.

For the full monitoring workflow that covers affordable housing alongside all other obligation types, see The Complete Guide to S106 Monitoring for Planning Officers.

Sources

• National Planning Policy Framework
• Town and Country Planning Act 1990, Section 106
• GOV.UK — Planning Obligations Guidance
• PAS — Infrastructure Funding Statements

This guide covers the practical steps for moving from Excel-based S106 monitoring to structured tracking — whether you're adopting dedicated software, building a database, or restructuring your spreadsheets into something more maintainable.

This is general guidance, not a product recommendation or legal advice.

Why Spreadsheets Break at Scale

Spreadsheets work for S106 monitoring until they don't. The failure point is usually between 50 and 100 live agreements. Common symptoms:

• Version conflicts. Two officers update the same file. One overwrites the other's changes. Neither notices until an IFS discrepancy surfaces in December.
• Structural inconsistency. The officer who built the spreadsheet left three years ago. New obligations get recorded in a different format. Half the formulas are broken.
• No audit trail. A contribution amount changes from £150,000 to £175,000. When? Who changed it? Was it an indexation calculation or a correction? The spreadsheet doesn't say.
• No alerting. Conditional formatting can highlight rows with approaching deadlines — if someone opens the file and notices. Spend-by deadlines don't announce themselves.
• Flat data model. Spreadsheets are rows and columns. S106 monitoring needs a hierarchical structure: agreements contain obligations, obligations have triggers and financial terms, triggers link to development milestones. Forcing this into a flat table creates either very wide rows (30+ columns) or multiple linked sheets that break when someone renames a tab.

The frustration described by officers at Bristol City Council (700+ agreements across multiple spreadsheets — "not efficient or effective") and Wokingham Borough Council ("years of unsatisfactory work with Excel spreadsheets and duplication") on the PAS Knowledge Hub reflects a structural problem, not a skill problem. These are competent officers using the wrong tool.

Before You Migrate: Audit Your Current Data

Don't move bad data into a new system. Start by auditing what you have:

Step 1: Inventory Your Spreadsheets

List every file involved in S106 tracking:

• Main S106 register (the "master" spreadsheet)
• Financial tracking sheets (contributions received, allocated, spent)
• Monitoring sheets (trigger tracking, compliance checks)
• IFS compilation sheets
• Archive files (completed agreements)
• Any personal tracking files maintained by individual officers

You may find data in places you didn't expect. Officers often maintain personal copies when the shared file is unreliable.

Step 2: Assess Data Completeness

For each live agreement, check whether your data includes:

If obligations aren't listed separately — if the spreadsheet has one row per agreement with a notes column summarising the obligations — you have a significant restructuring task before any migration.

Step 3: Identify Data Quality Issues

Common problems to flag:

• Missing receipt dates (you have amounts but not when they arrived)
• Inconsistent obligation categorisation (is it "education" or "school" or "primary education"?)
• Broken formulas (especially indexation calculations)
• Duplicate records (the same agreement appears in multiple files)
• Missing agreements (signed but never added to the register)

Document these issues. They need to be resolved during migration, not after.

The Migration Process

Phase 1: Define Your Target Data Structure

Before moving any data, decide what your new structure looks like. At minimum, you need three levels:

Level 1: Agreement

• Planning application reference
• Site address
• Agreement date
• Parties
• Status (live / discharged / modified)

Level 2: Obligation

• Obligation type (financial / in-kind delivery / restriction)
• Purpose (education / highways / affordable housing / open space / etc.)
• Trigger type and milestone
• Financial terms (amount, indexation basis, base date)
• Spend-by period
• Status (pending / triggered / paid / allocated / spent / delivered / discharged)

Level 3: Transaction

• Date
• Type (trigger recorded / invoice issued / payment received / allocation made / spend recorded)
• Amount
• Reference
• Officer

This structure works whether you're building a database, adopting software, or even restructuring your spreadsheets.

Phase 2: Migrate Live Agreements First

Don't try to migrate everything at once. Start with live agreements only — those with active obligations.

For each agreement:

1. Extract each obligation as a separate record
2. Record the current status of each obligation
3. For financial obligations: record receipts, allocations, and spend to date
4. Calculate spend-by deadlines from receipt dates
5. Flag any obligations where data is missing (receipt date unknown, trigger status unclear)

Work through agreements in order of deadline urgency. Agreements with spend-by deadlines in the next 18 months are your priority.

Phase 3: Verify Against Source Documents

For any obligation where the spreadsheet data seems incomplete or contradictory, go back to the original agreement document. This is time-consuming but essential — migrating incorrect data into a new system gives you faster access to wrong information.

Priority verification:

• Financial amounts and indexation terms
• Spend-by periods (these are often in a general clause, not next to each obligation)
• Trigger wording (especially occupation thresholds — is it "prior to" or "upon"?)

Phase 4: Run in Parallel

Don't switch off the old spreadsheet on day one. Run the new system alongside it for one quarter — ideally a quarter that includes your IFS reporting period. Compare outputs. If the new system produces an IFS that matches your manual compilation, your migration is validated.

What to Do If You're Staying on Spreadsheets

If dedicated software isn't in the budget or procurement pipeline, you can still improve your spreadsheet-based monitoring significantly:

1. Restructure to obligation-level. One row per obligation, not one row per agreement. This is the single most impactful change.

2. Standardise field formats. Use a dropdown list for obligation types, not free text. Consistent categorisation makes reporting possible.

3. Add a receipt date column. If you only track amounts, add receipt dates. You can't calculate spend-by deadlines without them.

4. Create a deadline view. A filtered view showing all financial contributions sorted by spend-by deadline, highlighting anything within 18 months.

5. Lock structure, not data. Protect the column headers and formulas. Let officers edit data cells. This prevents the structural drift that makes spreadsheets unmaintainable.

6. Set up calendar reminders. For every contribution with a spend-by deadline, create a calendar event at the 18-month, 12-month, and 6-month marks. This is manual but better than nothing.

For a structured approach to deadline tracking, try the S106 Spend Deadline Calculator.

For the full monitoring process, see The Complete Guide to S106 Monitoring for Planning Officers.

Sources

• PAS Knowledge Hub — Section 106 Databases Discussion
• Town and Country Planning Act 1990, Section 106
• PAS — Infrastructure Funding Statements

This guide covers how the two systems interact from a monitoring perspective — what planning officers need to track, where they overlap, and where they diverge.

This covers England only. This is general guidance, not legal advice.

The Core Difference

S106 (Section 106 agreements) are negotiated, site-specific obligations under Section 106 of the Town and Country Planning Act 1990. Each agreement is bespoke. The developer commits to delivering or funding specific infrastructure tied to the impact of their development.

CIL (Community Infrastructure Levy) is a fixed-rate charge set by the council's charging schedule, applied to qualifying development based on floor area. It funds general infrastructure — the council decides where to spend it (subject to the reporting requirements in Schedule 2 of the CIL Regulations).

When Both Apply to the Same Development

On a qualifying development, both CIL and S106 can apply simultaneously. The developer pays CIL based on the charging schedule and enters an S106 agreement for site-specific obligations that CIL doesn't cover.

The critical rule: S106 cannot duplicate CIL. If your council's Infrastructure List identifies education as a CIL-funded infrastructure type, you generally cannot also seek an S106 education contribution from the same development for the same purpose. However, site-specific mitigation that goes beyond the general CIL provision can still be secured through S106.

In practice, most councils use:

• CIL for general infrastructure categories (strategic transport, community facilities, green infrastructure)
• S106 for site-specific requirements (affordable housing, direct access works, on-site open space, development-specific education provision)

The boundary isn't always clean. Planning officers need to know their council's Infrastructure List and apply it consistently when negotiating S106 terms.

What This Means for Monitoring

Different Data Models

S106 monitoring tracks individual obligations with triggers, financial terms, and spend-by deadlines. Each agreement is different. The data model is obligation-level, nested within agreements.

CIL monitoring tracks a standardised charge through a fixed lifecycle: liability notice → demand notice → payment → allocation → spend. The data model is transaction-level with uniform fields.

Trying to monitor both in a single spreadsheet format creates compromises. S106 needs flexible, obligation-level tracking. CIL needs structured, transaction-level tracking. Most councils end up with two separate systems — which is fine operationally but creates problems at IFS reporting time.

Different Deadlines

S106 contributions have spend-by deadlines defined in each agreement — typically 5–10 years from receipt. Miss the deadline and the developer can reclaim the money.

CIL has no statutory spend-by deadline. Once collected, the council can hold CIL indefinitely (though this raises questions about infrastructure delivery and transparency).

This means your deadline alerting system only needs to cover S106, but your IFS reporting needs to cover both.

Different Financial Tracking

S106 financial contributions are index-linked (usually BCIS or RPI) and the amount varies by agreement. You invoice the indexed amount at the trigger date.

CIL is calculated at the point of planning permission using the published rate, adjusted by the national BCIS index. The amount is fixed once the demand notice is issued.

Both need receipt tracking, but S106 requires more manual calculation at the invoicing stage.

IFS Reporting: Where S106 and CIL Converge

The annual Infrastructure Funding Statement requires separate sections for CIL and S106 — but both appear in the same published document. This is where having two separate monitoring systems creates the most friction:

• Section 2 (CIL Report) requires: receipts, expenditure, admin costs, neighbourhood portion, and retained balance
• Section 3 (S106 Report) requires: agreements entered into, money received, money spent, money retained, and non-monetary contributions delivered

If your CIL data lives in a billing system and your S106 data lives in a spreadsheet, compiling the IFS means extracting data from two places, reconciling it with a third (finance), and assembling it into a single document. This is why the IFS takes days at councils without structured monitoring.

For a step-by-step IFS compilation process, see How to Produce Your Infrastructure Funding Statement in Half the Time. You can also generate a starting template with the free IFS Template Generator.

The Neighbourhood Portion: A CIL-Specific Complication

CIL includes a mandatory neighbourhood portion: 15% of CIL receipts from developments in a parish area must be passed to the parish council (25% if the parish has an adopted neighbourhood plan). This doesn't apply to S106.

For monitoring purposes, you need to:

• Track which developments fall within parish boundaries
• Calculate and pass the neighbourhood portion within the required timeframe
• Report the amount passed in your IFS

Parishes can spend their neighbourhood portion on a wider range of purposes than the council can spend its share — including anything that addresses the demands of development in the area. But they must report on how they've spent it, which creates an additional tracking requirement.

Practical Implications for Planning Teams

If you manage both S106 and CIL:

1. Keep your Infrastructure List current. This is what determines whether an infrastructure type is funded through CIL (general charge) or S106 (site-specific). An outdated list creates double-dipping risks and legal challenges from developers.

2. Track S106 deadlines actively, CIL balances passively. S106 has financial consequences for missed deadlines. CIL does not. Allocate your monitoring effort accordingly.

3. Align your data structures for IFS reporting. Even if you use separate systems for S106 and CIL, standardise the reporting fields so your IFS compilation pulls from consistent data. Use the same infrastructure categories in both systems.

4. Record the relationship between CIL and S106 on each application. When a development pays CIL and has an S106 agreement, note this on both records. This prevents confusion about which contribution funds which infrastructure item.

5. Use the IFS as a data quality check. If your IFS numbers don't reconcile, you have a monitoring problem that extends beyond reporting. Fix the underlying data issue, not just the IFS.

For an overview of S106 monitoring processes, see The Complete Guide to S106 Monitoring for Planning Officers.

Sources

• Town and Country Planning Act 1990, Section 106
• Community Infrastructure Levy Regulations 2010
• Community Infrastructure Levy (Amendment) (England) (No. 2) Regulations 2019
• PAS — Infrastructure Funding Statements
• GOV.UK — Planning Obligations Guidance

If you're a planning obligations officer setting up monitoring for new agreements, these examples show what to record and what to watch for.

This covers England only. This is general guidance, not legal advice. Refer to the specific terms of each agreement.

What an S106 Agreement Typically Contains

A Section 106 agreement is a deed executed between the developer, the landowner, and the local planning authority. The structure varies by solicitor, but most agreements follow a similar pattern:

1. Recitals — the planning application reference, site description, and reason for the obligation
2. Definitions — key terms used throughout (Commencement, Occupation, Index-Linked)
3. Planning obligations — the substantive commitments, listed as individual obligations
4. Schedules — detailed terms for each obligation type (financial contributions, affordable housing, highways works)
5. Plans — site plans showing the land to which the agreement relates

The obligations section is what you'll spend most of your monitoring time on. Each obligation needs to be extracted and tracked individually.

Example 1: Financial Contribution — Education

Typical wording:

"The Owner shall pay to the Council the Education Contribution of £287,500 (index-linked to the BCIS All-in Tender Price Index from the Base Date) prior to Occupation of the 50th Dwelling."

What to record for monitoring:

Monitoring pitfalls:

• Indexation is routinely miscalculated. The base amount is not the amount you invoice. You need to apply the index from the base date to the invoice date. On a £287,500 contribution, a 15% index movement adds £43,125 — real money left on the table if you invoice the base figure.
• "Prior to occupation" is ambiguous without a notification mechanism. How do you know when the 50th dwelling is occupied? Check whether the agreement requires the developer to notify the council, or whether you need to monitor building control completion certificates.
• The spend-by clock starts at receipt, not at the trigger date. If the developer pays six months after the trigger, your deadline calculations need to reflect the payment date.

Example 2: Affordable Housing Delivery

Typical wording:

"The Owner shall not Occupy or permit Occupation of more than 50% of the Market Dwellings until the Affordable Dwellings have been constructed and transferred to the Registered Provider in accordance with Schedule 3."

What to record for monitoring:

Monitoring pitfalls:

• Tenure mix substitution. Developers sometimes deliver all units as shared ownership when the agreement specifies a mix. Check the schedule carefully and verify the tenure of delivered units with the registered provider.
• "Constructed and transferred" is two steps. Units can be built but not transferred. The obligation isn't discharged until both conditions are met. If the registered provider pulls out, the developer still owes the obligation.
• Phased schemes complicate triggers. On a 500-unit scheme delivered in 3 phases, "50% of market dwellings" might mean 50% of the total or 50% of a phase. The wording matters — read it literally.

Example 3: Highways Works

Typical wording:

"The Owner shall prior to Commencement enter into a Section 278 Agreement with the Highway Authority for the Highways Works as shown on Plan 3 and shall complete the Highways Works prior to Occupation of the first Dwelling."

What to record for monitoring:

Monitoring pitfalls:

• Two separate triggers. The S278 agreement must be signed before commencement. The works must be completed before first occupation. If development commences without the S278, you have a breach — but enforcement action takes months.
• Highways works often slip. Developers will occupy dwellings before highways works are complete. Your monitoring needs to flag when the completion trigger has passed but works are still outstanding.
• Adoption takes years. Highways authorities require a defects liability period (typically 12 months) before adopting completed works. Until adoption, the developer remains responsible. This is usually a highways authority issue, but your S106 register should record the completion date and adoption status.

Example 4: Open Space Commuted Sum

Typical wording:

"The Owner shall pay to the Council the Open Space Maintenance Sum of £150,000 upon Transfer of the Open Space Land to the Council."

What to record for monitoring:

Monitoring pitfalls:

• Land transfer and maintenance sum are linked but separate. You can't invoice the maintenance sum until the land is transferred. But the developer might delay the transfer if the open space isn't laid out to specification. Track both obligations together.
• Maintenance periods are long. Commuted maintenance sums cover 10–25 years of upkeep. The council's parks team needs to confirm they can maintain the space before accepting the transfer.

What to Check Before Signing Off on Monitoring Setup

When a new S106 agreement arrives, use this checklist before adding it to your register:

• Every obligation extracted as a separate tracked item
• Trigger type and milestone identified for each obligation
• Financial amounts recorded with indexation basis and base date
• Spend-by period identified (check the clawback clause — it's often in a general provisions schedule, not alongside each obligation)
• Developer notification requirements noted (must they notify you of triggers, or must you monitor independently?)
• Service area contacts assigned for each obligation type (education, highways, housing, parks)
• Agreement added to building control watch list for commencement and occupation monitoring

For a customised version of this checklist tailored to your agreement's obligation types, try the S106 Agreement Checklist Generator.

For the broader monitoring process, see The Complete Guide to S106 Monitoring for Planning Officers.

Sources

• Town and Country Planning Act 1990, Section 106
• GOV.UK — Planning Obligations Guidance
• PAS — Infrastructure Funding Statements Guidance

This is the question that keeps planning obligations officers awake in December — and it's the question that spreadsheet-based monitoring systems answer poorly, if at all.

This guide covers how S106 spend-by deadlines work, what happens when they're missed, and how to build a deadline tracking process that prevents your council from returning developer money.

This covers England only. This is general guidance, not legal advice. Always refer to the specific clawback terms in each S106 agreement and consult your legal team on repayment obligations.

How S106 Spend-By Deadlines Work

Most S106 agreements include a clawback clause: if the council doesn't spend a financial contribution within a specified period, the developer can demand it back — often with interest. The legal basis for these obligations sits within each individual agreement, but GOV.UK planning obligations guidance sets out the broader framework for how planning obligations should be drafted and enforced.

The mechanics vary by agreement, but the typical structure is:

• Trigger: A development milestone (commencement, occupation of the Nth dwelling, phase completion) activates the obligation
• Payment: The developer pays the contribution (usually indexed to BCIS or RPI)
• Spend-by period: The council has a fixed period — typically 5 to 10 years from receipt — to spend the money on its specified purpose
• Clawback: If unspent after the deadline, the developer can request a refund of the unspent portion, sometimes with interest

The spend-by clock starts at receipt, not at the trigger point. This matters because there can be months between the trigger activating and the developer actually paying. If you're tracking deadlines from the wrong starting date, your calculations are wrong.

What Happens When a Deadline Is Missed

The Developer Requests a Refund

The clawback clause in the S106 agreement is a contractual right. When the spend-by period expires, the developer (or their successor in title) can write to the council requesting return of unspent funds.

The council's legal position depends on the exact wording of the agreement:

• Automatic refund clauses require repayment on expiry with no council discretion
• Request-based clauses require the developer to actively request a refund — if they don't ask, the money stays (but this is not something to rely on strategically)
• Interest provisions may add simple or compound interest from the date of receipt — turning a £200,000 clawback into £230,000+ depending on the rate and duration

Not every developer will request a refund. Some won't notice, some won't bother, some will have dissolved. But with the Home Builders Federation actively publicising the scale of unspent contributions, developers are increasingly aware of their clawback rights.

The Reputational and Political Cost

Beyond the direct financial loss, missed deadlines create:

• Audit findings. External auditors review S106 holding accounts. Contributions past their spend-by date with no allocation are flagged.
• Member scrutiny. Councillors asking why developer money intended for a new playground was returned to a housebuilder because nobody tracked the deadline.
• Community impact. The infrastructure that contribution was meant to fund doesn't get built. Residents see the development but not the promised school places, highway improvements, or open space.

The January 2026 Parliamentary debate on the S106 system explicitly raised the issue of unspent contributions — this is now a matter of national political attention, not just local operational risk.

Why Deadline Tracking Breaks Down

Problem 1: No Receipt Date Recorded

The spend-by clock starts on receipt. But many councils record the obligation amount and the agreement date — not the date the money actually arrived in the holding account. Without a receipt date, you can't calculate when the deadline expires.

Fix: When finance confirms an S106 receipt, immediately record the receipt date against the specific obligation. This is a 2-minute task that prevents a six-figure problem.

Problem 2: Deadlines Calculated But Not Monitored

Some councils have a "spend-by date" column in their spreadsheet. That's a start. But a date in a column is not an alert system. Nobody opens the spreadsheet on the first of every month to check which deadlines are approaching.

Fix: Deadline management needs active alerts — at 18 months, 12 months, 6 months, and 3 months before expiry. Whether that's calendar reminders, automated emails, or a dashboard with a countdown view, the deadline must find the officer — the officer shouldn't have to go looking for it.

Problem 3: Allocation vs Spend Confusion

A contribution is "safe" from clawback when it's spent — not when it's allocated. Earmarking £150,000 for a school extension project doesn't stop the spend-by clock. The money needs to be disbursed — invoices paid, contracts completed, evidence recorded.

Councils often allocate contributions to a project years before the project actually spends the money. If the project is delayed and the contribution sits allocated-but-unspent past the deadline, the developer can still request a clawback.

Fix: Track spend status separately from allocation status. An allocated contribution with an approaching deadline needs escalation to the service area responsible for the spend decision.

Problem 4: Service Area Disconnection

The planning team tracks the obligation. The finance team holds the money. The education team (or highways, or parks) decides how to spend it. None of these teams share a system, and none of them are watching the deadline.

Fix: Each obligation type needs a named service area contact who receives deadline alerts alongside the monitoring officer. If the education contribution has 12 months left and the education team hasn't committed to a project, the planning team needs to escalate — not wait and hope.

Building a Deadline Tracking Process

Step 1: Audit Your Current Exposure

Pull every financial contribution currently held by the council. For each one, record:

Sort by spend-by deadline. Everything within 18 months is your immediate priority.

Step 2: Categorise by Risk

• Red — deadline within 12 months, not fully spent: Escalate immediately. Identify a project, confirm commitment from the service area, and establish a spend timeline.
• Amber — deadline within 12–24 months, not fully allocated: Escalate to the service area for allocation. Monthly check-ins on project readiness.
• Green — deadline beyond 24 months or fully spent: Monitor quarterly. No immediate action needed but don't lose track.

Step 3: Establish Alert Cycles

Set up recurring alerts for every financial contribution:

• 18 months before deadline: Initial alert to monitoring officer and service area contact. Confirm allocation.
• 12 months: Escalation if not allocated. Service area must confirm a project and spend timeline.
• 6 months: Senior officer escalation if allocated but not yet spent. Project team confirms spend is on track.
• 3 months: Final escalation. If spend is not imminent, consider whether partial allocation can be demonstrated.

Step 4: Report Quarterly

Run a quarterly at-risk report for senior leadership:

• Total contributions at risk (deadline within 18 months, not fully spent)
• Total value at risk
• Actions taken since last report
• Contributions successfully spent or allocated
• Any clawback requests received

This report takes 30 minutes if your data is structured. It takes a full day if you're working from spreadsheets with inconsistent formats.

The Numbers That Matter

A few calculations that put S106 deadline risk in context:

• A council holding £2 million in S106 contributions with an average spend-by period of 7 years has roughly £285,000 reaching deadline each year
• If 20% of at-risk contributions are clawed back, that's £57,000 per year returned to developers — money that was meant to fund infrastructure your residents were promised
• The cost of a single large education contribution clawback (£300,000–£500,000) dwarfs the annual cost of any monitoring system

The question isn't whether deadline tracking is worth the effort. It's whether your council can afford not to do it properly.

For the full monitoring process including deadline management, see our complete guide to S106 monitoring.

Need to check your deadlines right now? Use the free S106 Spend Deadline Calculator — enter receipt dates and spend-by periods to see exactly when each deadline expires, with calendar export.

S106Ledger is building automated deadline alerts and financial tracking — so your team sees approaching deadlines weeks in advance, not after the developer's solicitor sends a letter. Join the waitlist for early access.

Sources

• Town and Country Planning Act 1990, Section 106
• Home Builders Federation — Section 106 Agreements and Unspent Developer Contributions
• Hansard — Planning: Section 106 System Debate (January 2026)
• GOV.UK — Planning Obligations Guidance
• PAS — Infrastructure Funding Statements

This guide sets out the evaluation criteria that matter for smaller English district councils and unitary authorities — the 150–200 LPAs managing 50–500+ live agreements without the budget or procurement bandwidth for enterprise systems.

This is general guidance, not a product recommendation or legal advice.

Why Spreadsheets Fail at S106 Monitoring

Spreadsheets aren't inherently bad. For a council managing 20 live agreements, a well-structured Excel file with conditional formatting is workable. The problems emerge at scale:

• No alerts. Excel doesn't send you an email when a spend-by deadline is 90 days away. Conditional formatting only works if someone opens the file and looks.
• No audit trail. When a value changes, you can't see who changed it, when, or what it was before. For financial tracking subject to audit queries, this is a gap.
• No multi-user access. Shared files on network drives create version conflicts. SharePoint and OneDrive help but don't solve the structural problem — the data model is still flat.
• No structured reporting. Producing your annual Infrastructure Funding Statement means manually filtering, pivoting, and cross-referencing. Every year. From scratch.
• No integration. Trigger point data comes from building control. Financial receipt data comes from your finance system. In-kind delivery data comes from service areas. A spreadsheet can't pull from any of these automatically.

The tipping point for most councils is between 50 and 100 live agreements. Below 50, spreadsheets are painful but manageable. Above 100, they're a liability.

The Seven Criteria That Matter

1. Obligation-Level Tracking

The most important feature — and the one most tools get wrong — is the data model. S106 monitoring is not agreement-level. It's obligation-level.

A single S106 agreement can contain 12 or more individual obligations: financial contributions to education, highways, open space, community facilities, plus in-kind obligations like affordable housing delivery and junction improvements. Each obligation has its own trigger, its own terms, its own deadline, and its own status.

Any monitoring tool worth using must let you:

• Record each obligation as a separate tracked item within an agreement
• Assign a trigger type and milestone to each obligation independently
• Track financial obligations through the full lifecycle: due → received → allocated → spent
• Track non-monetary obligations through: agreed → commenced → delivered
• Filter and report at the obligation level, not just the agreement level

If the tool treats each agreement as a single record with a notes field, it's a database — not a monitoring system.

2. Deadline Alerts

Spend-by deadline management is the highest-value feature for most councils. The consequences of missed deadlines are direct and financial — developers can reclaim unspent contributions, often with interest.

What to look for:

• Automated alerts at configurable intervals (12 months, 6 months, 3 months, 1 month)
• Alerts sent via email — not just displayed in a dashboard nobody checks daily
• Escalation capability — flag overdue items to a manager or senior officer
• A clear view of all contributions approaching deadline, sorted by urgency

A tool without deadline alerts is not solving the problem that costs councils the most money.

3. Financial Ledger

S106 financial tracking is more complex than a simple income/expenditure record. The tool needs to handle:

• Indexation. Most S106 contributions are index-linked. The tool should record the indexation basis (BCIS, RPI, CPI) and either calculate the indexed amount or flag when indexation needs applying.
• Split receipts. Developers often pay a single lump sum covering multiple obligations. The tool must allow you to split a receipt across obligations and record each allocation separately.
• Spend tracking with evidence. When a contribution is spent, you need to record what it was spent on, the date, and the amount — with enough detail to satisfy an audit query or a developer asking where their money went.
• Clawback tracking. If a contribution is returned to a developer (because a spend-by deadline was missed or an obligation was modified), that needs to be recorded as a distinct transaction.

4. IFS Generation

If you're compiling your annual Infrastructure Funding Statement manually from spreadsheets, it takes days. The right monitoring tool should generate your IFS — or at least the S106 section of it — directly from the data you've been maintaining all year.

Minimum requirements:

• Export of all S106 contributions received, spent, allocated, and retained during the reporting year
• Breakdown by infrastructure type
• Non-monetary obligations status report
• Ability to filter by financial year (1 April – 31 March)

If the tool stores structured data at the obligation level (criterion 1), IFS generation becomes a reporting function rather than a data-compilation project.

5. Self-Serve Setup

Enterprise S106 monitoring systems exist — they serve larger councils with dedicated IT teams and procurement budgets. For smaller councils, the implementation model matters as much as the feature set.

Look for:

• No IT department required. The planning team should be able to set up and use the tool without raising a service request.
• Data import. You have years of S106 data in spreadsheets. Any tool should accept a structured CSV import to avoid months of manual re-entry.
• Training requirements proportionate to team size. If a tool requires 3 days of paid training for a 2-person planning team, the implementation cost outweighs the benefit.
• Pricing below formal procurement thresholds. Many councils can direct-award contracts below their standing-order threshold (often £5,000–£10,000, though this varies by authority). A tool priced above this triggers a formal procurement process that can take months.

6. Data Ownership and Export

Council data is public data. Any tool you use must give you:

• Full data export at any time, in a standard format (CSV, Excel)
• No lock-in — your data is yours, and you can leave without losing it
• Clear data processing agreements (for GDPR compliance)
• UK-hosted or UK-adequate data storage

This matters more than it seems. If a vendor goes out of business or raises prices, you need to be able to extract your data and move on. If the only way to get your data out is to ask the vendor to run a custom export, you're locked in.

7. Reporting and Dashboards

Beyond the IFS, your tool should help you answer routine questions without manual analysis:

• How much S106 money are we holding, and how much is at risk of clawback?
• Which agreements have unrecorded trigger points (obligations due but not yet invoiced)?
• What's our total obligation exposure across all live agreements?
• Which service areas have allocated but unspent contributions?

A dashboard isn't a nice-to-have. It's how you make S106 monitoring visible to leadership — and how you justify the monitoring function's existence when budgets are reviewed.

Build vs Buy vs Status Quo

For smaller councils, the decision isn't really "which tool" — it's whether to invest at all. Three paths:

Keep the spreadsheet. Viable for councils with fewer than 50 live agreements and a monitoring officer who has built institutional knowledge. The risk is succession — when that person leaves, the knowledge goes with them.

Build a custom database. Some councils have built Access databases or SharePoint solutions. This works until the person who built it leaves, or the council's IT policy changes, or the database outgrows its original design. Maintenance cost is hidden but real.

Buy dedicated software. The right choice when you're managing 50+ agreements, have spend-by deadlines you can't afford to miss, and spend days on IFS reporting. The cost of the tool is typically less than the cost of a single missed deadline clawback.

The decision comes down to risk tolerance and team size. If a missed spend-by deadline on a single large contribution would cost more than a year's software subscription, the business case writes itself.

Evaluation Checklist

Use this when assessing any S106 monitoring tool:

• Obligations tracked individually within agreements, not as a single record
• Automated deadline alerts via email at configurable intervals
• Financial tracking through the full lifecycle with indexation support
• IFS report generation from structured data
• Self-serve setup without IT department involvement
• Full data export in standard formats
• Dashboard showing total obligations, at-risk amounts, and upcoming deadlines
• Pricing within direct-award procurement limits
• UK data hosting

For the broader monitoring workflow these tools support, see our complete guide to S106 monitoring.

S106Ledger is designed for planning teams at smaller councils who need structured monitoring without enterprise pricing. Join the waitlist to be notified when it launches.

Sources

• Town and Country Planning Act 1990, Section 106
• Community Infrastructure Levy Regulations 2010
• PAS — Infrastructure Funding Statements Guidance
• GOV.UK — Planning Obligations Guidance

This guide breaks down exactly what your IFS must contain, where to find each data point, and how to structure your monitoring data so the IFS becomes a report you generate — not a project you dread.

This covers England only. This is general guidance, not legal advice. Confirm reporting requirements with your legal team.

What the IFS Is and Why It Exists

The Infrastructure Funding Statement is an annual report that every local planning authority in England must publish under Regulation 121A of the Community Infrastructure Levy Regulations 2010 (inserted by the 2019 Amendment Regulations). The first IFS was due by 31 December 2020.

The IFS replaced the former Regulation 123 list and serves two purposes:

1. Transparency — showing residents and developers how S106 and CIL money is collected, held, and spent
2. Accountability — demonstrating that contributions fund the infrastructure they were intended for

The reporting period covers the previous financial year (1 April to 31 March). So the IFS published by 31 December 2026 covers the 2025/26 financial year.

What Schedule 2 Requires You to Report

Schedule 2 of the CIL Regulations sets out the minimum reporting requirements. Here's what you actually need to produce, split into the three required sections:

Section 1: Infrastructure List

A statement of infrastructure projects or types that the authority intends to fund (wholly or partly) through CIL and/or S106. This is the strategic forward look — what you plan to spend developer contributions on.

You need:

• Named infrastructure projects or categories (education, highways, open space, affordable housing)
• Whether funded by CIL, S106, or both
• Approximate amounts allocated or anticipated

Section 2: CIL Report

If your council charges CIL, this section covers the financial year:

• Total CIL receipts
• Total CIL expenditure (with project breakdown)
• CIL retained and unspent
• Administrative expenses (up to 5% of CIL receipts)
• Amount passed to parish/town councils (neighbourhood portion)
• Amount of CIL applied to repay borrowing

Section 3: S106 Report

This is where most councils struggle. The S106 report must include:

• Total money received through planning obligations during the reporting year
• Total money spent during the reporting year, broken down by infrastructure type
• Total money retained (received but not yet spent) — including amounts received in previous years still held
• Non-monetary contributions agreed and delivered — affordable housing units, highway works, open space, community facilities
• S106 obligations entered into during the reporting year (number and summary of terms)

The non-monetary contributions section is consistently the hardest to compile. Affordable housing delivery data sits with the housing team. Highway works completion data sits with the highways authority. Open space delivery data sits with parks and leisure. None of these teams are thinking about your IFS in November.

The Five-Step IFS Compilation Process

Step 1: Confirm Your Data Sources (October)

Before you start compiling, map out where each data point lives:

Start contacting service area leads in October. Give them a specific data request with a deadline of mid-November. Do not wait until December to ask.

Step 2: Reconcile Financial Data (November)

The most common IFS error is a mismatch between what planning records show was received and what finance records show was banked. These diverge because:

• Contributions arrive as a lump sum covering multiple obligations — finance records the payment, planning needs to split it across obligations
• Indexation adjustments mean the recorded "amount due" differs from the "amount received"
• Some councils hold S106 money in a single holding account, making it hard to match receipts to specific agreements

Reconciliation means matching every S106 receipt in the finance system to a specific obligation in your monitoring records. If you can't match them all, note the discrepancy and resolve it — don't fudge the numbers.

Step 3: Compile Non-Monetary Contributions (November)

For each S106 agreement with in-kind obligations, you need to report whether the obligation has been:

• Agreed — in a signed S106 agreement
• Commenced — work started or units under construction
• Delivered — completed and accepted/adopted

This requires direct confirmation from service areas. Send a structured template — not a free-text email request. A simple table works:

Step 4: Draft and Cross-Check (Late November)

Assemble the three sections. Cross-check:

• Do total receipts match between your S106 records and the finance system?
• Does the "retained" figure equal previous retained + this year's receipts − this year's spend?
• Are all agreements signed in the reporting year listed?
• Have you accounted for contributions returned to developers (clawbacks)?
• Does the CIL section reconcile with CIL billing records?

The PAS IFS guidance includes a checklist of required information — use it as a final verification pass.

Step 5: Publish and Archive (December)

Publish on your council's website by 31 December. The regulations require publication on the authority's website — no specific format is mandated. Most councils publish a PDF document, but some publish the data alongside an interactive dashboard.

After publication:

• Archive the source data that produced the IFS — you may need it for audit queries or developer disputes
• Note any data gaps or reconciliation issues to resolve before the next cycle
• Update your monitoring process to close the gaps that made this year's compilation difficult

What Makes This Take So Long — and How to Fix It

The councils that spend 3–5 days on their IFS share common patterns:

Problem: Unstructured monitoring data. Obligations recorded as free text rather than structured fields. Fix: standardise your S106 register so every obligation has a type, a financial value, a trigger, and a status — discrete fields, not paragraph descriptions.

Problem: No receipt-to-obligation matching. Money arrives but nobody records which obligation it satisfies. Fix: when finance confirms a receipt, immediately match it to the specific obligation and record the receipt date. This is also critical for spend-by deadline tracking.

Problem: Late service area data requests. Asking the housing team for delivery data on 15 December gets you a hurried, incomplete response. Fix: send a structured template in October with a mid-November deadline. Follow up.

Problem: Year-on-year reinvention. Each year's IFS is compiled from scratch rather than rolling forward the previous year's data. Fix: maintain a persistent monitoring dataset that rolls forward. Next year's IFS should start with this year's "retained" figure and add new activity.

IFS Data That Doubles as Monitoring Intelligence

The IFS isn't just a compliance exercise. The data you compile for it answers questions your planning committee and senior leadership should be asking:

• How much S106 money is sitting unspent? If the answer is growing year on year, you have a spend-rate problem — and spend-by deadlines are approaching.
• Which obligation types are consistently under-delivered? If highway works are routinely "commenced" but never "delivered," there may be an enforcement issue.
• What's the average time from receipt to spend? If it's more than 3 years, contributions are at risk of clawback.

If your IFS data is well-structured, these questions become queries you can answer in minutes rather than investigations that take days.

For a complete overview of the monitoring process that feeds into your IFS, see our guide to S106 monitoring for planning officers.

Need a starting point right now? Try the free IFS Template Generator — enter your council's data and download a structured template in PDF format.

S106Ledger is building automated IFS generation from live monitoring data — your annual report compiled in minutes, not days. Join the waitlist for early access.

Sources

• Community Infrastructure Levy Regulations 2010 (including Schedule 2)
• Community Infrastructure Levy (Amendment) (England) (No. 2) Regulations 2019 — inserted Regulation 121A (IFS requirement)
• PAS — Infrastructure Funding Statements Guidance and Sample Template
• GOV.UK — Publish Your Developer Contributions Data

This guide covers the practical reality of S106 monitoring — what you actually need to track, where monitoring typically fails, and how to build a process that stops contributions falling through the cracks.

This guide covers England only. This is general guidance, not legal advice. Always refer to the specific terms of each S106 agreement and consult your legal team on enforcement matters.

What S106 Monitoring Actually Involves

Section 106 of the Town and Country Planning Act 1990 allows local planning authorities to enter planning obligations with developers. Most guidance online focuses on negotiating these agreements — explaining what they are to homebuyers and developers. That's not what this guide is about.

For planning teams, the harder work starts after the agreement is signed. S106 monitoring means tracking every obligation from agreement to discharge. That covers six distinct activities:

• Agreement registration — recording terms, parties, land parcels, and each individual obligation as a separate tracked item
• Trigger point tracking — monitoring development milestones (commencement, occupation thresholds, phase completion) that activate obligations
• Financial tracking — recording contributions due, received, allocated to projects, and spent
• Deadline management — tracking spend-by periods (typically 5–10 years from receipt) before contributions must be returned to developers
• Compliance verification — confirming in-kind obligations (affordable housing units, highway works, open space) are delivered to the agreed specification
• Annual reporting — producing the Infrastructure Funding Statement required under the Community Infrastructure Levy Regulations 2010 (as amended)

Most planning officers know the list. What's less obvious is the scale of what goes wrong when monitoring breaks down.

Where S106 Monitoring Fails — and What It Costs

The Home Builders Federation found that the 171 councils surveyed — roughly half of all LPAs — held £2.8 billion in unspent S106 contributions, suggesting the true national figure is substantially higher. That includes contributions at risk of being returned to developers because spend deadlines are approaching or have already passed.

Officers at Bristol City Council reported managing 700+ live S106 agreements across multiple spreadsheets — describing the system as "not efficient or effective." Wokingham Borough Council described "years of unsatisfactory work with Excel spreadsheets and duplication." Both accounts were shared on the PAS Knowledge Hub S106 database discussion thread, which has drawn responses from planning officers across the country.

These aren't outliers. At most smaller district councils — the 150–200 LPAs managing 50–500+ live agreements — S106 tracking lives in a combination of spreadsheets, shared drives, and institutional memory. When a monitoring officer leaves, half the knowledge goes with them.

The consequences are specific:

• Missed spend deadlines mean developers can reclaim contributions — often with interest. A single missed deadline on a large education contribution could cost a council hundreds of thousands of pounds.
• Unrecorded trigger points mean contributions go uncollected. If a development reaches its 50th occupation and nobody records it, the indexed financial contribution tied to that milestone never gets invoiced.
• IFS reporting becomes a crisis. Regulation 121A of the CIL Regulations (inserted by the 2019 Amendment Regulations) requires every LPA to publish an annual Infrastructure Funding Statement by 31 December. Compiling this from unstructured spreadsheets takes days — and the accuracy is questionable.

The January 2026 Parliamentary debate on the S106 system confirmed this remains a live political issue, with the government signalling a full reset of S106 processes.

The Five Pillars of Effective S106 Monitoring

1. Structured Agreement Registration

Every S106 agreement should be recorded with a consistent structure the moment it's signed:

• Planning application reference and site address
• Agreement date and parties
• Each individual obligation listed separately — not buried in a paragraph summary
• Obligation type: financial contribution, in-kind delivery, restriction, or specific action
• Trigger point for each obligation, linked to a development milestone
• Financial terms: amount, indexation basis, payment schedule, spend-by period
• Responsible officer

The mistake most councils make is recording the agreement as a single entry. An agreement with 12 obligations needs 12 tracked items, each with its own trigger, deadline, and status. Thirty minutes of structured data entry per agreement saves days of forensic spreadsheet archaeology later.

2. Trigger Point Tracking

Triggers activate obligations. Common types:

• Commencement — development starts (usually evidenced by a commencement notice or building control notification)
• Occupation thresholds — e.g., "prior to occupation of the 50th dwelling"
• Phase completion — phased developments trigger different obligations at each stage
• Time-based — "within 12 months of commencement"

The challenge is that planning officers don't automatically know when these milestones occur. You need a process for receiving trigger notifications — whether from building control, site visits, or developer notifications required by the agreement.

Cross-referencing building control commencement and completion data against your S106 register monthly is the single most impactful process improvement for most councils. Missed triggers are the top source of lost contributions.

3. Financial Tracking

Financial contributions flow through four stages:

1. Due — trigger activated, contribution owed
2. Received — payment received from developer (check indexation)
3. Allocated — earmarked for a specific project or infrastructure
4. Spent — funds disbursed, evidence recorded

Each transition needs a date, a reference, and an audit trail. The spend-by deadline clock typically starts at stage 2 (receipt), not stage 1 (trigger).

Indexation catches out many councils. Most S106 financial contributions are index-linked — commonly to the BCIS All-in Tender Price Index or RPI. The amount due at the trigger point is the indexed amount at the date of calculation, not the base figure in the agreement. If you invoice the base figure, you're under-collecting.

4. Deadline Management

Spend-by deadlines are the highest-risk element of S106 monitoring. The pattern varies by agreement, but typically:

• Developer pays contribution upon trigger
• Council has 5–10 years to spend it on the specified purpose
• If unspent after the deadline, the developer can demand a refund — often with interest

With 200+ live agreements, each containing multiple financial obligations with different receipt dates and spend periods, you can have hundreds of active deadlines running concurrently.

Effective deadline management means:

• Recording the exact spend-by date for every financial contribution at the point of receipt
• Flagging contributions approaching their deadline at 12 months, 6 months, and 3 months
• Escalating at-risk contributions to senior officers and relevant service areas
• Maintaining an audit trail of allocation and spend decisions

For a detailed guide to the clawback process and how to build a deadline tracking system, see S106 Spend Deadlines: What Happens When Developer Money Expires.

5. Infrastructure Funding Statement Reporting

Since December 2020, every LPA must publish an annual IFS covering the previous financial year. Schedule 2 of the CIL Regulations sets out the minimum reporting requirements: S106 obligations entered into, contributions received, allocated, spent, and retained.

If your monitoring data is well-structured, the IFS should be a report you generate — not a project you start in November. The councils that struggle with IFS are invariably the ones whose underlying monitoring data is fragmented across spreadsheets with inconsistent structures.

The IFS also requires data on non-monetary obligations — affordable housing units delivered, highway works completed, open space provided. This is often the hardest data to compile because in-kind delivery is tracked (if at all) by service areas outside the planning team.

Building a Monitoring Process That Works

The gap between the five pillars above and what most smaller councils actually do is significant. Closing it doesn't require a large budget — it requires consistency:

1. Break every agreement into individual obligations at the point of signing. Don't summarise. List each obligation with its own trigger, terms, and deadline. This takes 30–60 minutes per agreement but prevents the data gaps that cause missed contributions later.

2. Set up monthly trigger checks. Cross-reference building control commencement and completion data against your S106 register. If you do nothing else on this list, do this.

3. Record receipt dates, not just amounts. The spend-by clock starts when money arrives. If you don't record the receipt date, you can't calculate the deadline.

4. Assign service area contacts for each obligation type. Education contributions need a named person in the education team who confirms allocation and spend. Highways contributions need a highways contact. Without ownership, contributions sit in holding accounts because nobody makes the spending decision.

5. Run a quarterly at-risk review. Pull every contribution with a spend-by deadline within 18 months. Confirm allocation status. Escalate anything unallocated. This is a 2-hour quarterly exercise that prevents six-figure refund demands.

S106 Monitoring Checklist

Use this to audit your current monitoring process:

• Every S106 agreement is broken into individual obligations with separate tracking
• Each obligation has a recorded trigger point type and development milestone
• Financial contributions are tracked through due, received, allocated, and spent stages
• Indexation basis is recorded and applied when invoicing
• Spend-by deadlines are calculated and recorded at the point of receipt
• Deadline alerts are set at 12, 6, and 3 months before expiry
• Building control data is cross-referenced monthly against S106 triggers
• Each obligation type has a named service area contact responsible for spend decisions
• Quarterly at-risk reviews are conducted for contributions approaching deadline
• IFS data can be extracted without manual compilation
• Non-monetary obligation delivery is recorded with evidence

If your monitoring process doesn't cover all of these, you have gaps that will cost your council money — either in returned contributions or in officer time spent firefighting. For a framework to evaluate monitoring tools, see What to Look for in S106 Monitoring Software.

For a deeper look at the IFS process, see How to Produce Your Infrastructure Funding Statement in Half the Time. You can also try the free IFS Template Generator, S106 Spend Deadline Calculator, and S106 Agreement Checklist Generator.

S106Ledger is building structured S106 tracking with deadline alerts, financial ledger, and one-click IFS reporting — designed for planning teams at smaller councils. Join the waitlist for early access.

Sources

• Town and Country Planning Act 1990, Section 106
• Community Infrastructure Levy Regulations 2010
• Community Infrastructure Levy (Amendment) (England) (No. 2) Regulations 2019 — inserted Regulation 121A (IFS requirement)
• Home Builders Federation — Section 106 Agreements and Unspent Developer Contributions
• PAS Knowledge Hub — Section 106 Databases Discussion
• PAS — Infrastructure Funding Statements Guidance
• Hansard — Planning: Section 106 System debate (January 2026)
• National Planning Policy Framework — Decision-making (Planning Obligations)