Lease Length Impact
Estimate how a short lease depresses value using relativity.
Introduction
Who this is for: Buyers and owners of leasehold flats assessing the effect of a shortening lease.
Why it matters: Value falls away sharply as a lease shortens, and the decline accelerates below 80 years — the point at which marriage value becomes payable on extension. Most lenders will not lend below about 70 years remaining, which shrinks the buyer pool further.
Typical scenario: A buyer weighing a flat with 74 years unexpired against the cost of extending.
- Assuming value declines in a straight line — it does not, it accelerates.
- Missing the 80-year threshold, crossing which materially increases extension cost.
- Underestimating how mortgage availability collapses on short leases.
Inputs
Property
years
Analysis
With 74 years unexpired, relativity is approximately 90.0%, valuing the flat at £288,000 against £320,000 with a long lease — £32,000 of value tied up in the lease length. Marriage value: payable (below 80 years). Mortgage availability: available, some lenders decline.
This analysis provides context, not financial advice. Consult a qualified adviser before making investment decisions.
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Sensitivity
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Live Results
Relativity
90.00%
Value with Current Lease
£288,000
Value Lost to Lease Length
£32,000
Marriage Value
Payable (below 80 years)