Planning application
26/03339/FULL
9 Chester Mews London SW1X 7AH
Proposal
Excavation of an additional basement level, in connection with the upgrade and enlargement of commerical space (Use Class E).
As published by the council, reference 26/03339/FULL
Timeline
Dates from the published record
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20 May 2026
Received by Westminster
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27 May 2026
Validated
Checked as complete and ready for consideration.
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21 Jul 2026
Added to PlanIndex
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Decision
Awaiting decision
The statutory target is eight weeks for most applications and thirteen for major development. Extensions of time are common.
What happens while it is decided
The process from here
This application is with Westminster for determination. The council publicises it, consults neighbours and technical bodies where required, and weighs the responses against local and national planning policy.
The statutory target is eight weeks for most applications and thirteen for major development, though extensions of time are common. Comments carry most weight while the case is undecided, so check the council portal for the deadline if you want to respond.
About full applications applications
How this application type works
A full application seeks permission for a complete, detailed proposal in one go: siting, design, access and landscaping are all fixed at this stage. It is the standard route for new buildings, conversions and changes of use. The statutory target is eight weeks for smaller schemes and thirteen weeks for major development, though complex cases often take longer by agreement.
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