The 21 day consultation period and how it runs
Twenty-one days from the site notice, not from registration. How publicity works, what happens to late comments, and when amended plans trigger re-consultation.
The planning consultation period on most applications is 21 days, and it starts when the council publicises the application rather than when it receives it. That gap matters. An application registered on a Monday may not have a site notice on the lamp post until the following week, and the 21 days runs from the date that notice went up, or from the date a neighbour letter was posted, whichever route the authority chose. If you want to comment, find the publicity date on the register rather than counting from validation.
Nothing about the period is negotiable in theory and quite a lot of it is flexible in practice.
Where the requirement comes from
Publicity requirements sit in article 15 of the Development Management Procedure Order 2015. The Order sets out which applications get which treatment: a site notice or neighbour notification for ordinary applications, and additionally a notice in a local newspaper for major development, for development affecting a listed building or a conservation area, for schemes accompanied by an environmental statement, and for departures from the development plan.
The authority chooses between a site notice and neighbour letters for most applications. Many use both, some use one, and the choice is a matter for the council rather than a right belonging to a neighbour. That surprises people who assume a letter is guaranteed.
Representations have to be received within the period stated, which is 21 days from the display of a site notice or the service of a neighbour letter, with a shorter period running from the date a newspaper advertisement appears. The register normally shows the dates and the deadline.
When the clock starts
Three dates get confused, and only one of them matters for your comment.
| Date | What it is | Does it start the consultation clock |
|---|---|---|
| Receipt | When the application arrives | No |
| Validation or registration | When it is accepted as valid and the determination period begins | No |
| Publicity | When the site notice is displayed, the letter served, or the advertisement published | Yes |
The determination period, eight weeks for most minor applications and 13 weeks for majors, runs from validation. The consultation period runs from publicity. They overlap, and on a slow week the publicity date can be several days after validation.
Where a site notice is taken down early by a passer-by, the authority can re-post it and restart the period. Where a letter goes to the wrong address, the same applies once someone notices.
Site notices, letters and press advertisements
A site notice has to be displayed on or near the land, in a position where it can be read by the public, and left up for the period. In practice notices get removed, covered or faded, and photographing one when you see it is worth doing if you later want to argue about the period.
Neighbour letters go to adjoining occupiers. Adjoining means sharing a boundary, so a house across the street or diagonally behind is often not notified even though it is more affected. If you are in that position, do not wait: check the register weekly for applications near you, since many authorities publish a weekly list.
Press advertisements matter for the categories listed above, and the date of publication starts the shorter period, so for a listed building application the press notice date is the one to watch.
Our notes on who must be told and site notices and neighbour letters go through the routes in more detail.
Late comments and whether they are considered
The statutory period is a minimum, not a cut-off. An authority must take into account material considerations at the time it makes the decision, so a comment received before the decision is made ought to be considered, and most councils will accept one until the officer report is signed off.
What changes as time passes is practical weight. Once the report is drafted, a late point has to be strong enough to make the officer rewrite a section. Once the decision notice is issued, it is too late, and the only routes left are the appeal, if the applicant appeals, or a complaint about process.
So send it inside 21 days. If you cannot, email the case officer, say a submission is coming and by when, and ask them to confirm they will consider it. A short email with a date in it is much more effective than a long letter that arrives after the report.
Statutory consultees run on their own timetable. The highway authority, the lead local flood authority, the Environment Agency and Historic England are consulted separately and usually have 21 days to respond, and their responses appear on the register as they arrive. Reading them is worth more than reading the applicant's documents, because a consultee objection is the thing most likely to change the recommendation.
Re-consultation on amended plans
There is no statutory duty to re-consult when an applicant amends a scheme during determination. Authorities have a discretion, guided by fairness: if the amendment introduces something a neighbour could not have commented on, re-consultation is the right course, and if it reduces the impact, often it is not.
In practice you will see one of three responses. A fresh 21 days where the change is substantial. A shorter period, commonly 14 or 7 days, notified to those who commented. Or no re-consultation at all, with the officer recording that the amendment reduces the effect.
If plans change and you were not told, say so in writing straight away, referring to the revised drawing numbers and dates. Authorities do correct this when it is raised early, and a complaint after the decision achieves much less.
Consultation on a revised description
A changed description of development is different from a changed drawing. If the description changes in a way that alters what is being applied for, the application has effectively become a different application, and re-advertising is normally required. Adding a storey, changing the number of units, or changing the use are the obvious cases.
Small clarifications, such as correcting a street name or the spelling of a building, do not need it. The test the officer applies is whether anybody reading the original description would have been misled about what was proposed.
If you were never notified
Take these steps in order:
- Check the register for the publicity method used, the dates and the deadline.
- Comment now, whatever the dates say, and ask the officer to confirm receipt.
- Ask the authority which properties were notified and why yours was not.
- Check the council's published statement of community involvement, since it may commit the authority to more than the statutory minimum.
- If the decision has been made, ask for the officer report and consider a complaint to the authority and then to the Local Government and Social Care Ombudsman.
Being unnotified rarely invalidates a permission by itself, and challenging a grant of permission means judicial review, with short deadlines and real costs. Complaints about process are more realistic, and where the same failure keeps happening they do change practice.
Where consultation on a large scheme is the issue, applicants are usually expected to do their own engagement as well, which the Statement of Community Involvement page explains. Our note on what happens to objections after consultation follows the comment through to the decision.
This is general guidance, not legal advice; check the position with your local planning authority or a qualified professional before relying on it.
Frequently asked questions
Does the 21 days run from when the application was submitted?
No. It runs from publicity: the date a site notice was displayed, a neighbour letter served, or, for applications needing a press advertisement, the date of publication. The determination period of eight or 13 weeks runs from validation instead, so the two clocks start on different days and the register shows both.
Am I entitled to a letter about a neighbour's application?
Not necessarily. The Development Management Procedure Order lets the authority choose between a site notice and neighbour notification for most applications, and neighbour letters go to adjoining occupiers, meaning those sharing a boundary. A house across the street may be more affected and still not notified, so check the weekly list yourself.
Will the council consider a comment sent after the deadline?
Usually yes, if it arrives before the decision, because the authority must take account of material considerations when it decides. Most councils accept comments until the officer report is finalised. Practical weight falls away as time passes, so email the case officer, say when your submission will arrive, and ask them to confirm they will consider it.
Must a council re-consult on amended plans?
There is no statutory duty, only a discretion exercised for fairness. Substantial changes usually attract a fresh 21 days, lesser changes a shorter period notified to those who commented, and reductions in impact often none. If plans change and you were not told, write immediately quoting the revised drawing numbers and dates.
What if the description of development changes?
A changed description that alters what is being applied for, such as adding a storey, changing unit numbers or changing the use, normally requires re-advertising because it is in substance a different application. Corrections to spelling or a street name do not. The test is whether a reader of the original description would have been misled.
Sources and further reading
This article is general guidance about the planning system in England and, where stated, the rest of the UK. It is not legal or professional advice. Check your local planning authority’s validation requirements and take professional advice for your specific site.