🗓 Submission Timing Intelligence
When is the best month — and weekday — to submit your planning application? Real approval-rate + decision-speed data from 25,848 dated decisions across UK LPAs.
📊 Hillingdon
Months below refer to when you submit, not when the decision lands. Each application is bucketed by its received_date month — but the approval rate measures the final outcome, whenever it landed (60-90 days later typically). The lag is already baked into the signal: "submit in December = 100% approval" already accounts for the fact that those decisions arrive in Feb/March. The month-by-month table below shows the lag explicitly so you can see the full cycle.
🎯 Inverse view — "I want a decision in [month], when do I submit?"
Based on this LPA's typical decision-lag of 71 days (~2 months), the table below shows when to submit if you want your decision to land in a specific month.
| If you want a decision in... | Submit by (approx.) | That submit month's approval rate |
|---|---|---|
| Jan | Submit by end of Nov | 84.2% |
| Feb | Submit by end of Dec | 89.4% |
| Mar | Submit by end of Jan | 88.6% |
| Apr | Submit by end of Feb | 90.7% |
| May | Submit by end of Mar | 100% |
| Jun | Submit by end of Apr | 100% |
| Jul | Submit by end of May | 100% |
| Aug | Submit by end of Jun | 100% |
| Sep | Submit by end of Jul | 75% |
| Oct | Submit by end of Aug | 60% |
| Nov | Submit by end of Sep | 86.4% |
| Dec | Submit by end of Oct | 75.6% |
Inverse calculation is approximate — actual decision time varies (range typically ±30 days). Use the Decision Time Predictor for tighter forecasts.
⏱ Decision speed by application type
How long different application types actually take at Hillingdon. Householder apps are statutorily 8 weeks; full/major are 13 weeks — but the real numbers usually drift. This is what the data says, not what the statute says.
→ Fastest: Prior Approval (41 days). Slowest: Full / Major (85 days).
| Application type | Decisions | Approval rate | Avg days | Range | |
|---|---|---|---|---|---|
| Householder | 288 | 89.9% | 67 d (10 wk) | 28–268 d | Filter ▸ |
| Lawful Development | 136 | 91.9% | 50 d (7 wk) | 7–270 d | Filter ▸ |
| Full / Major | 96 | 66.7% | 85 d (12 wk) | 38–343 d | Filter ▸ |
| Prior Approval | 33 | 93.9% | 41 d (6 wk) | 25–116 d | Filter ▸ |
| Conservation Area | 28 | 85.7% | 61 d (9 wk) | 32–113 d | Filter ▸ |
| Advertisement | 24 | 91.7% | 63 d (9 wk) | 50–95 d | Filter ▸ |
| Listed Building | 11 | 100% | 64 d (9 wk) | 44–87 d | Filter ▸ |
📅 Month-by-month breakdown — full submit→decide cycle
Each row shows the complete journey for applications received in that month: how long they took, when the decision actually landed, and what % were approved. The approval rate already accounts for everything that happens between submission and decision — the lag is part of the signal.
| Submit month | Decisions | Approval rate | Median lag | Decision typically lands in | Range |
|---|---|---|---|---|---|
| January | 202 |
88.6%
|
50d (~7wk) | → March | 7–77d |
| February | 75 |
90.7%
|
48d (~7wk) | → April | 10–316d |
| March | 8 |
100%
|
17d (~2wk) | → April | 10–28d |
| May | 6 |
100%
|
258d (~37wk) (outlier) | → February | 249–268d |
| June | 3 |
100%
|
250d (~36wk) (outlier) | → February | 206–273d |
| July | 4 |
75%
|
209d (~30wk) (outlier) | → February | 152–266d |
| August | 10 |
60%
|
173d (~25wk) | → February | 141–217d |
| September | 22 |
86.4%
|
139d (~20wk) | → February | 99–195d |
| October | 45 |
75.6%
|
97d (~14wk) | → January | 65–154d |
| November | 133 |
84.2%
|
64d (~9wk) | → January | 39–127d |
| December | 208 |
89.4%
|
57d (~8wk) | → February | 22–112d |
Read across each row: submit in [month] → wait [median lag] → decision lands in [target month] → outcome [approval rate]. The approval rate is the final outcome of the whole cycle, not a snapshot.
🗓 Day-of-week patterns
| Day received | Decisions | Approval rate | Avg days |
|---|---|---|---|
| Monday | 203 | 89.7% | 69 |
| Tuesday | 146 | 85.6% | 72 |
| Wednesday | 144 | 83.3% | 75 |
| Thursday | 113 | 86.7% | 84 |
| Friday | 122 | 88.5% | 70 |
📊 Data sources & freshness
Timing is a tactical edge, not strategic justification. Use alongside the constraint check + pattern fingerprint to make the case strong on substance, then time it to land well.
- planning_applications.received_date (updated Daily ingest)
25,848 dated decisions where both received_date and decision_type are known. Approval = approved/granted/permit. Sample size gating: months with fewer than 8 decisions excluded from best/worst recommendation. - Day-of-week patterns
Reflects when applicants choose to submit, which may correlate with applicant type (Monday = professional consultants; Friday = end-of-week DIY submissions). Causality is correlative not causal. - Decision-time outliers
Months showing 200+ day averages are flagged — they reflect older PINS-appeal-derived rows where determinations stretched over many months. Read the Jan/Feb/Nov/Dec numbers (largest samples) as the reliable benchmark.