Lease Extension Premium Calculator
An indicative range for the premium payable on a statutory lease extension of a flat, from the freeholder’s side.
Calculated under Schedule 13 to the Leasehold Reform, Housing and Urban Development Act 1993
An indicative range for the premium on a statutory lease extension. The valuation date is fixed on the date the section 42 notice is served, so figures should be taken as at that date.
Indicative premium range
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Relativity is derived from a curve based on the Savills 2015 and Gerald Eve 2016 unenfranchiseable graphs. This calculator produces an indicative range only. It is not valuation advice and must not be relied upon in responding to a notice or in setting a counter-notice figure. Relativity, deferment and capitalisation rates are matters of professional judgement and vary by property, location and evidence. Development value, defective leases, unusual ground rent provisions and improvements are not accounted for. The opinion of a specialist RICS Registered Valuer should always be obtained.
How the figure is arrived at
Valuation date
The section 42 notice fixes the valuation date. Values and rates are taken as at that date, not as at today, which matters where the notice was served some time ago.
Capitalised ground rent
The ground rent payable over the remaining term, capitalised at the capitalisation rate. This income ends on the grant of the new lease.
Diminution in the reversion
The freehold reversion is deferred over the existing term, and again over the term plus 90 years. The difference is the loss to the freeholder.
Marriage value
Where the unexpired term is below 80 years, the increase in the combined value of the two interests is currently shared equally. At 80 years or above it does not arise at all.
Relativity
Derived from a curve based on the Savills 2015 and Gerald Eve 2016 unenfranchiseable graphs. It can be overridden where the evidence supports a different figure.
A figure you can rely on
A calculator cannot inspect the flat, weigh the comparable evidence or judge the rates a tribunal would apply. If a notice has been served, or you are considering your position, send us the details and we will prepare a proper valuation.
Make an enquiry
A calculator gives you a range. If a notice has been served, or you want a figure you can rely on, send us the property address and the date of service.

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