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Expert Insights

How do I amend an existing planning consent?


I have an unimplemented planning permission for a mixed-use development in London, but in the light of changes in the market, I wish to substitute one of the permitted uses for a different commercial use. I am also worried that the permission might expire before I am in a position to put in the revised reserved matters that my new scheme would require, and I would like to extend the life of the permission. Can I use section 73 or section 96A of the Town and Country Planning Act 1990 to achieve my objectives?


If the desired change can be achieved without the need to amend the description of development (by amending a plans condition, for instance), then section 73 might be used to make the change. If a change of description is needed, then a non-material amendment application under section 96A is a possible route to change the description of development which might then be combined with a section 73 application.

However, extending the life of the permission would not be possible under section 73 and it is highly questionable whether section 96A could be used to achieve the same objective. The best course of action might be to use section 96A to change the phasing requirements of the scheme to allow implementation to take place without all the reserved matters needing to have been signed off.


Once a planning permission is granted, there are two main routes to its amendment. The first is to seek what amounts to the grant of a fresh planning permission under section 73 of the Town and Country Planning Act 1990. Section 73 planning permission is for the same development as the existing planning permission, but without compliance with all or some of the conditions to which the permission is subject. That means, for instance, that the scheme itself might be changed, by substituting different drawings for those listed in a planning condition as comprising the development.

Particular care, however, should be taken if the desired change would require a change to the description of the development, as set out in the planning permission itself. The Court of Appeal in Finney v Welsh Ministers [2019] EWCA Civ 1868; [2019] EGLR 56 decided that section 73’s ambit is limited to a consideration of conditions rather than the description of development. It found that, correctly construed, the statutory provision was intended to “give relief” from a condition or conditions, rather than enable (re)consideration of the scope of the development itself. It drew on Lord Carnwath’s view in Lambeth London Borough Council v Secretary of State for Housing, Communities and Local Government [2019] UKSC 33; [2019] EGLR 42 that section 73 was available for changes to condition in respect of the “same development”.

However, section 96A is already being employed to work around this difficulty. Section 96A can be used to make “non-material” amendments to a planning permission. It is possible that a change of description (unless radical in nature) would fall within that definition – that is a matter of planning judgment. Once the new desired use has been substituted for the existing use in the description of development, the problem caused by Finney ceases to be an obstacle.

Extending the life of the permission

The issue is rather more difficult where extending the life of the permission is concerned. The deadline for lawful implementation of a planning permission is usually set out in a condition and was in the past regularly extended through making a section 73 application to amend the condition, but parliament then legislated to prevent section 73 being used for that purpose.

Can section 96A come to the rescue here too? That will depend on whether changing a permission so as effectively to extend the time for implementation counts as “non-material”. In practice, there have been some cases where such an application has been permitted, but care needs to be taken: in R (on the application of Fulford Parish Council) v City of York Council [2019] EWCA Civ 1359; [2019] EGLR 45 the Court of Appeal said of section 96A:

“The one condition that cannot be dispensed with under this power is a condition limiting the time within which development must be begun or an application for the approval of reserved matters must be made: section 73(4). Section 96A should not be interpreted so as to override section 73(4).”

It seems likely that the court was here referring to section 73(5), rather than 73(4), given the way the provision is described. It would be curious if a restriction to a relatively broad and far-reaching power like section 73 could be overridden by a much narrower power like that in section 96A, so the risk posed by the decision in Fulford should be noted.

As for a pragmatic solution (if all of the reserved matters cannot feasibly be submitted before the due date), the best way forward would probably be to make an application under section 96A to introduce a phasing condition, or to amend an existing phasing condition, such that only some of the reserved matters need to be submitted before the permission can be lawfully implemented. In that way, there might be a greater chance of getting some reserved matters in to the local planning authority, and the permission being implemented lawfully in time.

This article was written by barrister Rupert Warren QC at Landmark Chambers and partner Helen Hutton at Charles Russell Speechlys LLP and was first published in Estates Gazette on 6 October 2020. For more information, please contact Helen on +44 (0)20 7203 5314  or at

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