Section 73: varying a condition without starting again
Section 73 varies conditions on an existing permission but cannot touch the description of development or extend a time limit. Here is where the line sits and what to submit.
A section 73 application asks the council to grant permission for the same development without complying with one or more of the conditions on an existing permission. It is the ordinary route for a minor material amendment, and it is quick, but it comes with a hard boundary that catches people every year: it cannot change the description of development. If the change needs the words on the front of the decision notice to say something different, section 73 is the wrong application.
The other point people miss is that a section 73 grant is a new permission in its own right. The original stays alive alongside it.
What section 73 allows
Section 73 of the Town and Country Planning Act 1990 lets an applicant seek permission to develop land without complying with conditions attached to an earlier permission. On such an application the authority may only consider the question of the conditions. It cannot revisit the principle of the development, and it cannot refuse on grounds unrelated to the conditions in issue.
If the authority decides that permission should be granted subject to different conditions, or to none, it grants a new permission accordingly. If it decides the existing conditions should stand, it refuses, and the original permission continues unaffected.
Typical uses are the ones that keep a live site moving: substituting revised drawings under the approved plans condition, adjusting a materials specification, altering hours of operation, changing a phasing sequence, or relaxing a condition that has become impossible to comply with.
The limits
Two limits do most of the work.
The description of development cannot be altered. The Court of Appeal settled this, and the consequence is practical rather than technical: a permission described as "erection of four dwellings" cannot become five by section 73, however the conditions are worded. Where the description itself specifies a quantum, a height or a use, that figure is fixed and only a fresh application will move it.
Time limits cannot be extended. Section 73 cannot be used to change a condition by extending the period within which development must be started, so a permission running out of time cannot be renewed this way. Apply before expiry, because once a permission has lapsed there is nothing left to vary.
Beyond those, the test the council applies is whether the amended scheme remains within the envelope of what was permitted. There is no statutory definition of a minor material amendment, and authorities take different views on where the line sits, which is one of the honest uncertainties of this route. Where the change would read as a different development to a neighbour standing in the street, expect resistance.
Section 73 or section 96A
Section 96A allows a non-material amendment. The change has to be so slight that it makes no material difference, judged against the permission as a whole and its context. A window repositioned on a rear elevation, a corrected drawing number, a minor dimensional adjustment.
The differences that matter in practice:
| Section 73 | Section 96A | |
|---|---|---|
| Effect | New permission, original survives | Amends the existing permission |
| Publicity | Normally consulted and publicised | No statutory consultation requirement |
| Determination period | Eight weeks | Twenty-eight days |
| Conditions | All conditions restated on the new grant | Existing conditions can be amended in step |
| Scope | Minor material amendment | Change with no material effect |
Fees for both are set in the national fee regulations and indexed annually, so take the current figures from the published schedule rather than an older article.
The Levelling-up and Regeneration Act 2023 inserted a further power, section 73B, allowing applications to alter an existing permission where the effect would not be substantially different. As at September 2026, check the commencement position and any regulations before assuming that route is available in your authority.
The new permission and its conditions
A section 73 grant is a standalone permission. Every condition that is still needed has to be restated on it, including the ones that were not in issue, because conditions do not carry across by implication. A decision notice that lists only the varied condition leaves the rest of the development uncontrolled, and a careful applicant checks the draft and asks for the omissions to be added.
Two consequences follow for the developer. The new permission has its own commencement position, so where the original was already implemented, the site is being built under one or the other and the paperwork should say which. And the levy position is recalculated, because Community Infrastructure Levy liability attaches to the permission being implemented and the chargeable floorspace may have moved.
Overlapping permissions on the same land need care for a separate reason. The Supreme Court has held that where a later permission is implemented and makes it physically impossible to complete an earlier one as approved, the earlier permission cannot lawfully be carried out to completion. On a phased site being amended piecemeal, that turns a paper question into a real one. Keep a schedule of which permission each plot is built under, and where a scheme is being varied in stages, consider whether a single section 73 covering the whole site is safer than a series of small ones.
Section 106 obligations do not automatically follow either. Where an agreement was tied to the original permission, a deed of variation or a fresh agreement is usually needed so that the obligations bind the new permission.
What to submit
Keep the application tight and make the officer's job easy:
- The application form identifying the permission reference, the exact condition numbers and the wording sought.
- A drawing pack with a clear schedule showing superseded and replacement drawings, with revision letters.
- A short planning statement explaining what has changed, why, and why the change stays within the scope of the original permission.
- Updated technical information only where the change affects it, such as revised drainage calculations or an updated daylight assessment.
- A tracked comparison of the original and proposed condition wording.
Where the change affects appearance or layout, an updated design and access statement or a short addendum to it saves an argument about whether the design rationale still holds.
Illustrative example: moving a plot boundary
A five-unit scheme has permission with an approved plans condition listing the site layout. During construction the developer wants to move the boundary between plots 3 and 4 by 1.5 metres to give plot 4 a wider driveway, which pulls plot 3's garden in and shifts one parking space.
This is illustrative rather than a real case. The description of development still reads "erection of five dwellings", so the quantum is unchanged. The change is confined to the layout drawing referenced in a condition. A section 73 application to vary the approved plans condition, substituting a revised site layout, is the right route, and the supporting statement should address the effect on plot 3's private amenity space against the council's standards and confirm the parking count is maintained.
Had the developer wanted a sixth dwelling in the same space, no amount of condition variation would deliver it. That is a fresh application.
This is general guidance, not legal advice. Check the position with your local planning authority or a qualified professional before relying on it.
Browse the report types on PlanScope to draft the supporting statement for a variation application. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.
Frequently asked questions
Can section 73 change the number of units?
Only if the number does not appear in the description of development. Section 73 cannot alter the description, so a permission described as the erection of four dwellings cannot become five by varying a condition. Where the description fixes a quantum, a height or a use, a fresh planning application is the only route to change it.
Can I use section 73 to extend a permission that is about to expire?
No. Section 73 cannot be used to change a condition by extending the period within which the development must be started, and once a permission has lapsed there is nothing left to vary. Apply before expiry, or make a fresh application for the same development if the deadline has already passed.
What is the difference between section 73 and section 96A?
Section 96A handles amendments so slight they make no material difference, is determined in twenty-eight days and amends the existing permission. Section 73 handles minor material amendments, is normally consulted on, takes eight weeks and results in a new standalone permission with all its conditions restated.
Does the original permission survive a section 73 grant?
Yes. The section 73 permission sits alongside the original rather than replacing it, so a developer holding both should record which one is being implemented. The new permission also has its own commencement position and its own levy calculation, and any section 106 obligations usually need a deed of variation to bind it.
Do all the old conditions carry over automatically?
No, and this is a common trap. Conditions do not transfer by implication, so every condition still needed has to be restated on the new grant. Check the draft decision notice and ask for anything missing to be added, because a permission that omits the drainage or landscaping conditions leaves that part of the development uncontrolled.
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.