Cross-boundary sites: applying to two councils at once

A cross boundary planning application is determined twice. Where a site straddles the boundary between two local planning authorities, each council determines the development within its own area, on its own development plan, to its own committee cycle. There is no single decision maker and no mechanism for one authority to decide the whole thing.

The duty to co-operate is often invoked at this point, and it does not help. That duty applies to plan-making, not to the determination of applications. What actually manages a split site is procedure: matched descriptions, matched drawings and a lot of diary work.

Where the boundary falls and who decides what

Start with the boundary itself, taken from the definitive administrative boundary rather than a title plan or an aerial overlay. Boundaries follow historic features, and a hedge that moved in 1974 can put a corner of the site in the wrong district.

Once the line is fixed, the rule is simple. Each authority determines the development that lies within its area. Both applications red-line the whole site, so the decision maker can see the scheme as a whole, but the blue land and the description make clear which built form each council is being asked to permit.

The failure case is a split decision, where one authority grants and the other refuses. The permission granted is real but unbuildable if the refused half contains the access or the drainage. That is an appeal against the refusal, not a renegotiation with the authority that granted.

Twin applications and matching descriptions

Submit two applications with an identical description of development. Not similar. Identical, word for word, including the unit numbers and floorspace figures for the whole site.

Where the descriptions drift apart, the two authorities end up permitting different developments, conditions conflict, and any later section 73 application has to be run twice against two different baselines. Officers will sometimes ask for a description limited to the part in their area. Resist it politely and instead describe the whole scheme and note which elements fall within that district, because that is what a decision notice needs to be enforceable against a plan.

Practical points that save weeks:

1. Use the same drawing numbers and revision letters in both submissions.
2. Number the documents identically so a condition listing approved plans reads the same on both notices.
3. Ask both authorities to agree a single set of conditions in draft before either goes to decision.
4. Keep one document register, shared with both case officers.

Two development plans, two policy tests

Each council applies its own adopted local plan, and section 38(6) of the Planning and Compulsory Purchase Act 2004 binds each to determine in accordance with its own plan unless material considerations indicate otherwise. Two plans can point in different directions on the same field.

Housing density, parking standards, open space requirements and affordable housing thresholds are the usual conflicts. One authority may require 40 per cent affordable housing above ten units while its neighbour applies a different threshold, and if the units sit unevenly across the line the arithmetic gets awkward.

Write the planning statement to address both plans in full rather than treating one as primary. A single Planning Statement submitted to both, with a policy compliance table for each authority, is easier for officers to work with than two documents that differ in wording, because the neighbouring officer will read the other council's copy.

Where the neighbouring authority is a county or a National Park, check which functions sit where before you assume. Minerals and waste applications go to the county, and National Park authorities are the planning authority for everything in their area.

Fees, CIL and obligations across the line

The fee regulations contain a rule for applications made to more than one authority for the same development, and it is not the same as paying twice in full. Confirm the calculation with both councils in writing before submission, and keep the correspondence, because a fee dispute at validation stops both applications rather than one.

Community Infrastructure Levy is different again. Each charging authority levies against the floorspace in its own area, under its own charging schedule and its own instalment policy. Two liability notices arrive, at two rates, and both councils must be told before work starts on site. Our guide to working out the fee you owe before you submit covers the application fee side of this.

For section 106, the cleanest structure is a single agreement to which both authorities are parties, with obligations expressed to be enforceable by each in respect of its own area. Two separate agreements work but create a risk of inconsistent triggers, and a trigger tied to occupation of a dwelling in the other district is unenforceable by the authority that did not sign.

Coordinating consultees and committee dates

The same statutory consultees will be consulted twice on the same scheme and may reply differently, particularly where the highway authority for each district is a different county council. Send them one consistent pack and tell them the site is split.

Committee dates are the harder problem. Two authorities with monthly cycles falling in different weeks can put six weeks between decisions even when both officers are content. Ask both case officers early whether the application is likely to be delegated or go to committee, and if committee, whether the two can be aligned. The difference between a committee and a delegated decision is worth understanding before you build a programme on it.

Where members on one side are minded to refuse, an extension of time on the other application is better than a granted permission that sits unusable while an appeal runs.

An illustrative case: access from the next district

Take a scheme of 18 dwellings where the housing sits entirely in District A and the only viable vehicular access crosses a paddock in District B. This example is illustrative.

District A determines the dwellings. District B determines the access road, the visibility splays and any works to its highway. B has no housing in front of it, so its interest is highways, drainage and landscape, and its own local plan policies on development in the countryside apply to the access strip.

Two things follow. The transport evidence has to satisfy two highway authorities, so scope it once with both in the room. And District B's decision is the critical path, because permission for houses without an access is worth nothing. Programme B first and treat A's determination as the follow-on.

Where the duty to co-operate actually bites

Section 33A of the Planning and Compulsory Purchase Act 2004 requires local planning authorities to co-operate on strategic cross-boundary matters when preparing plans. It has been the reason several local plans failed at examination, always at plan-making stage. The Levelling-up and Regeneration Act 2023 provides for its repeal and replacement with an alignment policy, though that repeal is not yet in force, so check the current position before citing it.

For an applicant, the practical value is in the evidence base. Statements of common ground prepared under the duty record what two authorities have agreed about housing need, employment land and infrastructure across their shared boundary, and those documents are quotable in a planning statement. Check the full list of supporting reports once you know which authority is asking for what.

This is general guidance, not legal advice; check the position with your local planning authority or a qualified professional before relying on it. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.