Extending your lease is one of the most important steps you can take to protect your property’s value and mortgageability. If your lease is under 100 years, its value may already be affected. Once it falls below 80 years, the cost of extending increases significantly due to marriage value.
Our free Lease Extension Calculator gives you an instant estimate of the premium payable under the Leasehold Reform, Housing and Urban Development Act 1993. It’s a quick, useful guide for leaseholders wanting to understand the likely cost of extending their lease before taking formal advice.
To generate your estimate, simply enter:
If you’re not sure about these rates, we recommend leaving them at the default settings. For experienced users, the calculator also allows adjustments to:
⚠️ Please note:
For any formal purpose, you will need a qualified valuation report prepared by our surveyors.
Our consultants can provide you with a tailored estimate that goes beyond the calculator. By completing the enquiry form on this page, you’ll receive:
Complete the form next to the calculator above and our team at Extension.Lease will provide clear, accurate advice to help you move forward with confidence.
The calculator provides a rough guide only. Lease extension valuations are complex and depend on detailed lease terms, local market evidence, and specialist judgment. Use this tool to get a feel for the likely costs, but always obtain a professional valuation before taking any formal action.
Usually, no but it depends on your specific circumstances. While reforms are expected to simplify the process and reduce costs in the future, marriage value still applies today for leases below 80 years, and premiums rise as time passes. There is no current guarantee that future reform will reduce the price payable. Acting sooner often saves money and protects your property’s value.
Marriage value is an additional cost that applies when a lease has fewer than 80 years remaining. It represents the increase in the flat’s value once the lease is extended, and the freeholder is entitled to 50% of that uplift.
These are technical rates used in lease extension valuations. The capitalisation rate converts the annual ground rent into a present value. The deferment rate is used to calculate the value of the property reverting to the freeholder when the lease ends. Our calculator uses standard defaults unless you choose to adjust them.
No. This tool is for guidance only and should not be used for formal legal or negotiation purposes. For that, you’ll need a qualified valuation prepared by a leasehold reform specialist
