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Lease Extension Calculator

Our lease extension calculator works out the premium to extend the lease on your flat, and carefully explains the process.
More accurate than you’ll find on any website, she’s an RICS qualified and registered valuer called Jackie Collis.

We don’t offer a lease extension calculator on our site because they are at best vague and at worst, misleading.

A property valuation for lease extension, or for freehold purchase, is made for a specific moment in time, for a specific given standard of maintenance. Every lease is different, with different terms, varying ground rents, boundaries of the demise, length of lease, and even details of the property itself.

Online lease extension calculators can offer a useful indicator, if your lease has over 80 years remaining, but they do not take account of rising ground rents and other important variables including intermediate interests. All of these will affect the final cost or premium to extend. If you are going to use one, we’d recommend going to the government ministry of housing website:

If you want to go ahead, you will then need professional advice and a professional valuation, with specific experience of residential lease extensions and collective enfranchisement. This is what we do. We work closely with your solicitor, or we can recommend a suitably experienced solicitor for you.

For no obligation initial advice or an initial quotation, please contact Jackie
on 01737 237 811 or email:

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