Evidence-gradeplanning AI.
AI built for the English planning industry: consultants, developers, land promoters, agents and councils. It answers from planning law, national policy and the development plan, and quotes the exact passage behind every point.
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It answers from the documents that decide a site, and says so when they do not. Advice you can act on and defend.
Question
How long do we have to submit reserved matters and commence development on an outline planning permission?
[1] TCPA-1990 · 92 Outline planning permission.
“(2) Subject to the following provisions of this section, where outline planning permission is granted for development consisting in or including the carrying out of building or other operations, it shall be granted subject to conditions to the effect—(a) that, in the case of any reserved matter, application for approval must be made not later than the expiration of three years beginning with the date of the grant of outline planning permission; and”
Verified 2 September 2026 · In force · Statute
One engine for the whole industry.
The same evidence, whoever asks.
England is decided in documents.
OTTO reads the ones that govern a site, so you argue from what they say, not from a summary of it.
National law and policy
Your district’s layer
Every document read in full, not summarised.
Don't take our word for it.
Each citation names its document and paragraph, and the source documents are public. The evidence sits with the answer, so the advice holds up when it is challenged.
Behind that sits a published benchmark that every release must pass before it ships. The results go up in full, pass or fail.
Read the benchmark →England's constraints, mapped.
The national layer is drawn from the planning register: Green Belt, National Parks and National Landscapes. Each district adds its own constraints, from conservation areas to Article 4 directions, and every one is weighed in the answer.
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