Financial Viability Assessments in Planning: A Complete Guide

If you’re applying for planning permission and can’t deliver full policy obligations, you’ll almost certainly need a financial viability assessment.

It’s the mechanism that determines how much a scheme can genuinely afford to contribute, most commonly toward affordable housing, but also Section 106 contributions, Community Infrastructure Levy, and other planning costs.

Get it right, and you unblock your planning consent with a negotiated, evidence-based position. Get it wrong and you’ll spend months arguing over numbers with the council’s independent reviewer. We’ve seen both outcomes plenty of times.

What Is a Financial Viability Assessment?

A financial viability assessment (FVA) is a standardised appraisal that tests whether a proposed development can meet its full planning obligations and still deliver a reasonable return to the developer and landowner.

The method is straightforward in principle.

You take the total scheme value, subtract all development costs and planning obligations, and see what’s left. If that residual figure falls below the benchmark land value (the minimum a reasonable landowner would accept to release the site) then the scheme can’t viably deliver everything the local plan asks for.

That’s the core of the residual method, and it underpins every FVA in England and Wales.

Three documents govern how this works: NPPF paragraph 59 (the policy), the Planning Practice Guidance on viability (the detail), and the RICS Professional Standard on financial viability in planning (the professional rules).

One thing that surprises a lot of applicants: not every scheme needs an FVA. The NPPF is clear that developments complying with up-to-date plan policies should be assumed viable. You only need one when you’re arguing your scheme can’t meet those policies in full. That’s an important distinction, because submitting an unnecessary FVA wastes time and money.

What Are the Key Inputs of Financial Viability Assessment?

Every FVA is built on four main inputs: gross development value, development costs, benchmark land value, and developer return. The PPG requires all of these to follow a standardised approach.

• Gross development value (GDV) is the total expected income from selling or renting the completed scheme. It must be based on current comparable evidence, meaning actual sales of similar new-build properties in the local area. Councils will challenge unsupported figures immediately, and rightly so. Aspirational pricing based on asking prices rather than completed transactions is one of the fastest ways to undermine your own assessment.
• Development costs cover build costs (the PPG recommends BCIS data as the benchmark), abnormal costs like contamination remediation or demolition, professional fees, finance costs, CIL, and contingency. Every figure needs to be site-specific and evidenced. A generic cost estimate pulled from an industry table won’t survive independent scrutiny.
• Benchmark land value (BLV) is where most FVAs succeed or fail. The PPG mandates the “EUV+” approach: take the land’s existing use value, add a premium that reflects the minimum a reasonable landowner would accept to sell, and that’s your benchmark. The price the developer actually paid for the land is irrelevant. The PPG states this explicitly, twice. Market transactions can cross-check your figure, but they can’t replace the EUV+ calculation.
• Developer return sits at 15–20% of GDV for market housing under the current PPG, with a lower figure appropriate for affordable housing given the reduced risk and guaranteed sale. The government’s latest NPPF consultation proposes standardising this at 17.5% for market housing and 6% for affordable.

BLV is the single most contested input in almost every FVA we work on. Developers who pay over the odds for a site and then try to use that price as the benchmark will be told, firmly, that the PPG doesn’t allow it. The assessment has to show what the land is worth in policy-compliant terms — not what someone chose to pay for it at auction.

What Does the Financial Viability Assessment Process Actually Look Like?

The applicant commissions the FVA, submits it with the planning application, and then the council appoints an independent reviewer to check every assumption. The applicant pays for that review.

The process typically runs like this.

You raise viability concerns in pre-application discussions (do this early, because surprises don’t help anyone). Then you commission the FVA from an RICS-qualified surveyor, who prepares it using the residual method with standardised inputs.

You submit it alongside your planning application. Some councils won’t even validate the application without it.

The council then appoints an independent viability consultant to review your assessment. This might be a specialist firm, or it might be the District Valuer through the Valuation Office Agency. They’ll go through every input: your GDV comparables, your build cost evidence, your BLV methodology, your profit assumptions.

If there are disagreements (and there usually are) you’ll go through rounds of written representations and meetings between both surveyors until a position is reached. Sometimes that’s full agreement. Sometimes it’s a compromise.

Sometimes both sides agree to disagree and the planning committee makes its own call.

Once a position is settled, the Section 106 agreement is drafted with review mechanism clauses. These are increasingly standard, particularly in London, and they allow the council to capture additional contributions if the scheme performs better than the FVA projected.

The whole process typically adds 3–6 months to the planning timeline. For a medium-scale residential scheme (10–50 units), expect total viability costs of roughly £15,000–£35,000: your own consultant’s fee plus the council’s independent review fee. Larger or more complex schemes cost significantly more.

Are Viability Assessments Public?

Yes. Since the July 2018 NPPF revision, all financial viability assessments should be prepared on the basis that they’ll be made publicly available.

Before 2018, FVAs were routinely treated as commercially confidential. That was a major source of public anger, particularly on high-profile London schemes where developers used viability arguments to reduce affordable housing from 35% to single digits behind closed doors. The policy shift was deliberate.

The PPG now states that information used in viability assessments is “not usually specific to that developer” and there’s rarely a genuine basis for keeping it confidential. In exceptional circumstances (genuinely sensitive ongoing land negotiations, for instance) an executive summary must still be published.

But in practice, full publication is now standard across most London boroughs and increasingly common elsewhere.

If you’re preparing an FVA today, assume it will be read by the public, ward councillors, local campaign groups, and journalists. That reality should inform how carefully you evidence every assumption.

What Makes the Difference Between a Good FVA and a Bad One?

Credibility. Every assumption needs to be evidenced, justified, and defensible under independent scrutiny.

The councils and independent reviewers who assess these reports do this every day. They know what reasonable inputs look like for their area. They know what BCIS says about build costs for the relevant property type. They know what comparable new-builds have actually sold for on neighbouring sites. An FVA that tries to inflate costs or deflate values to manufacture a viability gap gets challenged, delays the application, and damages your credibility on the next submission.

Common mistakes we see repeatedly: using the price paid for land as BLV (prohibited by the PPG), generic build costs without site-specific justification, GDV based on asking prices rather than completed sales, excessive contingency that doesn’t match the scheme’s actual risk profile, and no sensitivity analysis (which the RICS Professional Standard makes mandatory).

And there’s a subtler point. An FVA prepared by someone without RICS qualification carries less weight with planning officers, committee members, and inspectors.

The RICS standard requires a statement of objectivity, confirmation of no conflict of interest, and a declaration that fees aren’t contingent on the outcome. Those safeguards matter. They’re what separates a professional valuation from an advocacy document.

A well-evidenced, transparent report, even one that shows genuinely difficult numbers, moves through the system far faster than one that tries to game it.

A Practical Tool, Not a Loophole

A financial viability assessment isn’t about avoiding planning obligations. It’s about demonstrating, with proper evidence and standardised methodology, what a specific scheme can realistically deliver. The policy framework is clear, the process is well-established, and the expectations around transparency have never been higher.

If you’re preparing a viability case or need an independent review of one, get in touch with our team. We prepare and review FVAs for schemes across the UK, from small residential sites to major mixed-use developments.