London has one of the most complex leasehold systems in the world. Millions of flats — including thousands across Acton, Ealing, Chiswick, and the rest of West London — are owned on leasehold terms. When that lease drops below 80 years, the cost of extending it increases dramatically. Below 70 years, many mortgage lenders won't lend at all.
Our surveyors specialise in lease extension valuations for London leasehold flats.
What Is Leasehold and Why Does the Lease Length Matter?
When you buy a leasehold flat, you are buying the right to occupy the property for a fixed period — the lease term. The freeholder (landlord) retains ownership of the building and land. As the lease shortens, the value of your property falls and the cost of extending it rises — often sharply.
Key milestones to understand:
- Below 85 years: Mortgage lenders start to restrict, and buyers become wary
- Below 80 years: "Marriage value" kicks in — the most expensive threshold to cross
- Below 70 years: Many mainstream lenders will not offer mortgages
- Below 60 years: Very difficult to sell; premium increases significantly
Your Statutory Right to Extend
Under the Leasehold Reform, Housing and Urban Development Act 1993, qualifying leaseholders have a legal right to extend their lease by 90 years (added to the remaining term) and to have the ground rent reduced to a peppercorn (effectively zero). This is known as the "statutory route."
To qualify, you must:
- Have owned the property for at least two years
- Have an original lease term of at least 21 years
- Not be an Assured Tenancy
The Statutory vs Informal Route
You can also approach your freeholder informally (without triggering the statutory process) to negotiate a lease extension. This can sometimes be faster and cheaper — particularly if your freeholder is cooperative. However, without the statutory route, you have no legal right to the extension and the freeholder can dictate their own terms.
At Acton Surveyors, we advise most clients to begin with an informal approach — but to be ready to trigger the statutory process if negotiations stall.
The Lease Extension Process: Step by Step
Your surveyor calculates the "premium" — the amount you must legally pay the freeholder to extend. This is calculated using a complex formula set out in the 1993 Act.
Your solicitor serves a formal notice on the freeholder, triggering the statutory process and setting out your proposed premium. The freeholder has two months to respond.
The freeholder's surveyor responds with their valuation. Typically, this is higher than your figure. Negotiations begin between the two surveyors.
In most cases, the two surveyors reach an agreed premium without needing to go to tribunal. This can take 3–12 months depending on complexity.
If the parties cannot agree, either side can apply to the First-tier Tribunal (Property Chamber) to determine the premium. Tribunals are typically a last resort.
Once the premium is agreed and paid, your solicitor prepares and registers the new lease. You now have an extended lease with zero ground rent.
How Much Does a Lease Extension Cost in London?
The premium you pay varies enormously based on:
- The remaining lease length (shorter = more expensive)
- The property value
- The current ground rent
- The location and local market conditions
As a rough guide for West London flats in 2024–25:
| Remaining Lease | Approximate Premium |
|---|---|
| 90+ years | £2,000 – £8,000 |
| 85–90 years | £5,000 – £15,000 |
| 80–85 years | £10,000 – £25,000 |
| 75–80 years | £20,000 – £50,000 |
| Below 75 years | £40,000 – £100,000+ |
You'll also pay legal fees (£1,500–£4,000), your surveyor's fees (£1,000–£2,500), and the freeholder's reasonable legal and valuation costs.
Leasehold Reform 2024–25 Update
The Leasehold and Freehold Reform Act 2024 has made significant changes to the leasehold system in England and Wales. Key changes include:
- Abolition of the two-year ownership requirement to qualify for a statutory extension
- Removal of "marriage value" from the premium calculation (for leases under 80 years)
- Standardised valuation methodology
- Right to extend to 990 years (up from 90 years)
Many of these changes are not yet fully in force as secondary legislation is still being prepared. Our surveyors stay current with the evolving leasehold landscape — contact us for up-to-date advice.
Frequently Asked Questions — Lease Extensions
Can I extend my lease before I've owned the property for two years?
Under the 2024 Leasehold Reform Act, the two-year ownership requirement has been abolished for statutory extensions. You may now be able to serve a Section 42 notice immediately upon purchase. Check with your solicitor for the current position as regulations are still being implemented.
What is "marriage value" and why is it important?
Marriage value is the additional value created by the merger of the leasehold and freehold interests when a short lease is extended. Previously, when a lease dropped below 80 years, the leaseholder had to share 50% of the marriage value with the freeholder, making short lease extensions very expensive. The 2024 Act abolishes marriage value from the calculation.
Should I extend before or after buying a short lease flat?
You can ask the seller to serve the Section 42 notice before exchanging contracts, then assign the benefit of the notice to you at completion. This way you don't need to wait two years. Speak to your solicitor and surveyor about the best approach for your situation.
Does extending my lease increase the value of my flat?
Yes — typically significantly. A flat with 75 years remaining will be worth considerably less than the same flat with 125 years remaining, all other things equal. The cost of the extension is usually considerably less than the increase in property value it generates.
How do I know if my lease is short?
The unexpired lease term is stated in your lease documentation or land registry title register. If you're unsure, your solicitor or a surveyor like Acton Surveyors can check this for you quickly.
For specialist lease extension valuation services in West London, contact Acton Surveyors today. We provide RICS-compliant valuations and expert representation throughout the extension process.