London borough planning certainty measures how often a planning application receives a favourable decision within a fixed time window. According to the London Borough Planning Certainty Index from Authority Inc, 12,044 of 17,807 fully observed applications received a favourable recorded decision within 180 days in the 12 months to February 2026. That gives London a score of 67.6 out of 100, and the average hides a very wide spread between boroughs.
Quick Answer
London borough planning certainty is the share of comparable planning applications that receive a favourable recorded decision within 180 days of validation. The latest mature score is 67.6, up 3.6 points from February 2025. A higher score means timely approvals were more common. It does not mean more homes or commercial schemes were financed, started or completed.
What Does London Borough Planning Certainty Actually Measure?
Planning certainty is a narrow and precise measure. The index counts full planning applications, including those combined with listed-building or conservation-area demolition consent, handled by London’s 33 borough planning authorities. Each application is tested against one rule: was a favourable decision recorded within 180 days?
Three details make the measure useful for developers and investors.
A fixed clock
The 180-day window starts at validation and never changes. Later approvals and refusals do not count as timely favourable decisions, so the score rewards speed and outcome together.
Missing outcomes are not failures
Authority Inc only publishes a cohort when at least 80% of eligible applications have enough public evidence to score. The latest cohort had 88.6% outcome coverage. Applications with unknown outcomes are left out rather than treated as refusals.
A planning score, not a delivery score
Restaurant openings, housing starts and completed buildings are different things from planning decisions. Planning certainty tells you how predictable the consent stage was. Finance, legal agreements, conditions and construction must be assessed separately.
Is London Planning Certainty Improving?
Yes, on the measured evidence. The Authority Inc series shows the 12-month rate rising from 58.5 in December 2021 to 67.6 in February 2026. Most of that gain came after early 2024. The score moved from 60.3 in February 2024 to 64.0 in February 2025, then to 67.6 a year later.
The direction is clear, but the cause is not. Authority Inc is careful to say the index describes what happened, not why. An independent planning specialist quoted on the page, Isabella L.B., PhD, of AtkinsRéalis, points to several possible drivers:
- Lower application volumes, which may reduce pressure on planning teams and may also mean weaker schemes were never submitted.
- Higher fees and tighter deadlines, which probably helped but are unlikely to be the main cause.
- Backlogs built up through 2022 and 2023 by repeated changes to the system.
- The 2021 to 2026 grant-funding cycle, which may have pushed residential applicants to secure approvals before the March 2026 deadline.
The practical reading is that a rising average is encouraging but should be tested against the mix of applications, not taken at face value.
How Do London Boroughs Compare on Planning Certainty?
Borough planning certainty varies far more than the London average suggests. Authority Inc ranks 29 boroughs that have at least 100 fully observed cases and sufficient outcome coverage. The gap between the top and bottom is 46.5 points.
The most predictable boroughs
Wandsworth leads with 82.7, followed by Islington at 81.7, Camden at 79.6 and Southwark at 79.4. In these boroughs, roughly four in five observed applications received a favourable decision inside 180 days.
The middle of the field
Westminster scores 73.1 on 2,067 observed cases, the largest sample in the ranking. That matters because a high score on a big, varied caseload says more than a high score on a small one. Hackney (71.6), Tower Hamlets (71.2) and Newham (70.9) sit close together just below.
The least predictable boroughs
Harrow scores 36.2, Croydon 44.7 and Havering 45.5. Barnet, with 788 observed cases, scores 52.7. For an applicant, a score in the 30s or 40s means most comparable applications did not receive a timely favourable decision.
The takeaway is simple: the borough handling an application matters more than the London-wide number.
Authority Inc publishes borough comparisons only where the sample is large enough to be reliable. Smaller boroughs are withheld rather than ranked on thin evidence, which keeps the comparison honest but means not every borough has a public score.
Which Policy Changes Could Affect London Planning in Late 2026?
Three developments are shaping the outlook, according to the September 2026 edition of the Authority Inc analysis.
The Draft London Plan consultation
City Hall opened a 13-week statutory consultation on a streamlined London Plan running from 16 July to 15 October 2026. Borough local plans must stay in general conformity with the London Plan, so the draft gives applicants, councils and landowners a new reference point before the final plan is adopted.
The affordable-housing programme
On 21 July 2026, City Hall said its 2026 to 2036 affordable-housing programme was significantly overbid, and applicants were asked to revise bids around delivery confidence and value for money. Funding decisions do not change the planning score directly, but they can change which consented schemes remain commercially deliverable.
National station-area rules
On 17 August 2026, the government announced changes to fast-track housing near train, tram and Underground stations. London boroughs handle many station-area and mixed-use applications, so the rule could shift where schemes come forward and how density is judged.
None of these changes has yet appeared in a mature 180-day cohort. Their effect on decision speed is still to be observed, and the honest position is that nobody can say yet whether they will raise or lower the score.
Why Borough Averages Cannot Predict a Single Application
A borough score describes a population of past applications. It cannot tell you the fate of one live application. The Authority Inc data makes this visible through its 22 named live forecasts, locked on 25 August 2026, all of which remain unresolved.
Wandsworth is a useful example. It has the highest borough score in the ranking, yet its forecast approval probabilities for individual applications range from 37% to 91%. Site, scheme type, conservation constraints and application quality all shift the odds.
These forecasts are separate from the historical index and do not feed into the headline score. Prime residential applications use a 180-day outcome window, while hotel applications use 365 days. For decision-makers, the lesson is to combine three layers of evidence: the borough record, the application type and the specifics of the scheme.
How Should Developers and Investors Use Planning Certainty Data?
Planning certainty data works best as a screening tool, not a prediction. A few practical uses stand out.
- Sequence sites by borough risk. A scheme in a borough scoring above 75 has a very different timeline risk from one in a borough scoring below 45.
- Stress-test programme timelines. If a borough approves fewer than half of comparable applications within 180 days, financing and build schedules need more slack.
- Separate consent from delivery. Approval is one gate. Viability, funding and conditions can still stop a project.
- Watch the case mix. A rising score can reflect fewer, stronger applications rather than a faster system.
Authority Inc’s London planning intelligence is built around this distinction between measured planning outcomes and the wider question of whether projects get built.
The Takeaway for London Planning in 2026
London borough planning certainty has improved to 67.6 out of 100, but the London-wide figure is the least useful number in the dataset. The 46.5-point gap between Wandsworth and Harrow shows that location drives timeline risk more than any citywide trend. The Draft London Plan, affordable-housing funding and national station-area rules will decide whether the improvement holds, and the answer will only appear once newer cohorts complete their 180-day windows.
For anyone underwriting London schemes, the dependable approach is to use dated, methodologically consistent data such as the Authority Inc borough planning certainty index and to treat every score as evidence about the past, not a promise about the future.
Frequently Asked Questions
What is London borough planning certainty?
London borough planning certainty is the percentage of comparable planning applications that receive a favourable recorded decision within 180 days of validation. Authority Inc calculates it across London’s 33 borough planning authorities. A score of 67 means roughly 67 in every 100 observed applications met the rule.
Which London borough has the highest planning certainty?
Wandsworth has the highest score in the latest Authority Inc ranking at 82.7 out of 100, based on 738 observed cases. Islington (81.7), Camden (79.6) and Southwark (79.4) follow. Harrow ranks lowest of the 29 published boroughs at 36.2.
Does a favourable planning decision mean a project will be built?
No. Planning certainty stops at the recorded planning decision. Finance, legal agreements, planning conditions, construction and completion all sit outside the measure, and an approved scheme can still be delayed, redesigned or abandoned.
Why does the index use a trailing 12-month period?
A rolling 12-month window stops one unusually busy or quiet month from dominating the result. It also makes borough comparisons more stable, which is important because individual boroughs can have small monthly caseloads.
