Completion notices and development progress reporting

A completion notice is the power that lets a local planning authority put an end date on a permission that has been started and then left. It does not undo what has been built. It says that unless the development is finished within a stated period, which must be at least twelve months from service, the permission stops having effect for everything else.

For a developer running a phased scheme, that is the sharpest tool a council has against slow build out. It has historically been used rarely, because the procedure was cumbersome, and the Levelling-up and Regeneration Act 2023 set out to change that while adding two reporting duties at the front of the process.

As at September 2026, the reformed provisions depend on commencement regulations and on a development order specifying which permissions are caught. Check the current position on legislation.gov.uk before relying on any of it.

The completion notice power as it stands

Section 94 of the Town and Country Planning Act 1990 provides the mechanism. The authority serves a notice on the owner and occupier of the land, and on anyone else it thinks will be affected, stating that the permission will cease to have effect unless the development is completed within the period the notice specifies.

Three features are worth holding onto.

The notice bites on the unbuilt remainder. Buildings already erected under the permission remain lawful, and a completion notice cannot require their demolition. What it removes is the authority to carry on.

The minimum period is twelve months, and the authority can give longer. In practice the period is negotiated, because an authority that sets an unrealistic date invites a challenge and gains nothing.

And the notice can be withdrawn by the authority at any time before the period expires. That makes it a lever as much as a sanction. A notice served on a stalled site often produces a conversation about a revised programme rather than a lapsed permission.

The historic weakness was confirmation. A notice served by an authority had no effect until the Secretary of State confirmed it, which meant a hearing, delay and an uncertain outcome. Very few authorities thought it worth starting. The 2023 Act reforms move the power towards direct service with an appeal route, which is the change that could make it matter.

Commencement notices

The 2023 Act inserted a requirement to notify the local planning authority before development begins. The purpose is simple record keeping: authorities have often had no reliable way of knowing when a permission was implemented, which undermines monitoring, enforcement time limits and the completion notice power itself.

Do not confuse this with the commencement notice required under the Community Infrastructure Levy regulations. That one exists to fix the liability date, and missing it can cost a self-builder an exemption outright, as the procedure around the levy's own commencement notice shows. A site in a charging authority area may need both notices, served on different bases, at different times.

The practical instruction is unchanged whatever the commencement position turns out to be. Record the material operation that started the development, with dates, photographs and invoices, and keep it in the project file. Every argument in this area, from enforcement to lapsed permissions to levy liability, turns on when work began and on whether the operation relied on was lawful.

That last point catches people. Where a permission carries pre-commencement conditions that have not been discharged, digging a trench may not amount to a lawful start at all.

Development progress reports

The reporting duty is aimed at larger schemes. The Act allows a development order to specify which permissions are caught, what has to be reported and how often, with the expectation of an annual return setting out completions against the anticipated build out.

The point of it is transparency. Authorities have long argued that they cannot plan infrastructure or maintain a housing land supply position when they do not know whether a consented site will deliver 60 homes next year or six. Developers reply, with some justification, that build out is driven by sales rates and market absorption rather than by intent.

Both things are true. What the reporting duty changes is the record. Once an authority holds a series of annual returns showing a scheme delivering well below the trajectory in the officer report, it has evidence to use, whether in a housing land supply calculation, in a completion notice, or in deciding how to treat the next application.

The non-implementation power

Alongside the reporting duties, the 2023 Act created a power for an authority to decline to determine an application where the applicant has failed to carry out an earlier permission on the same land. It is discretionary and hedged with conditions rather than automatic.

Treat it as a reason to explain, in the planning statement, why an earlier consent was not built. Viability, a change in the market, a ground condition discovered after consent, a delayed utility connection. An authority with a plausible account in front of it is unlikely to reach for the power. An authority left to draw its own conclusions may.

Checking the commencement position on a site you are buying

Due diligence on a part-built site should establish four things before exchange. Whether the permission was lawfully implemented, and on what date. Whether any pre-commencement condition remained undischarged at that point. Whether a completion notice has been served or threatened. And whether the levy liability was fixed by a valid commencement notice, because an unpaid liability follows the land.

The planning history on the council's register will answer the first and third. The fourth usually needs a direct enquiry to the charging authority, and it is worth making in writing.

Risks for phased and long-running schemes

Long programmes accumulate exposure. A permission implemented in year one, with a spine road and a first phase built, can sit for a decade with three phases unbuilt and the permission technically live.

Four things reduce the risk. Keep the authority informed with a written trajectory, updated annually, whether or not a statutory duty applies. Discharge conditions phase by phase rather than in one late application. Use section 73 to update the scheme where the market has moved, instead of allowing the consent to become undeliverable. And watch the outline permission time limits in section 91 and 92, because a reserved matters approval that expires is a harder problem than a completion notice.

If a completion notice does arrive, the first question is whether the remaining development can realistically be finished in the period given. If it cannot, start work on the replacement application immediately rather than spending the twelve months arguing, because you will need the supporting documents a fresh application would need anyway and policy will have moved on since the original consent.

Reform in this area has been announced, legislated and brought into force in stages over several years, and the sequence is easy to lose track of. The planning law updates timeline is a reasonable place to follow what has actually taken effect.

Enter the site postcode on PlanScope to see which documents a replacement or amended application at your site is likely to need. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval. This is general guidance, not legal advice. Check the position with your local planning authority or a qualified professional before relying on it.