Why lease extension matters at auction
Properties with short leases sell at auction at a discount — that's the mechanism that brings them there. Sellers who can't get the full open market price on the conventional market because of the lease issue turn to auction where experienced investors expect to buy at a discount and factor in the cost of extending.
The problem is that many buyers don't know how to calculate that discount accurately. They see a flat on the guide price, bid what seems like a sensible price below comparable properties, and discover afterwards that the lease extension is going to cost £25,000 — making what seemed like a 20% discount a deal that broke even or lost money.
The rule for any leasehold lot with under 85 years remaining is simple: calculate the extension cost first, deduct it from the value of the equivalent property with a 999-year lease, and that is your maximum bid. The guide price is irrelevant to this calculation.
The two routes to lease extension
1. Statutory route (Leasehold Reform, Housing and Urban Development Act 1993)
Qualifications: must have owned the property for at least 2 years before serving a Section 42 Notice. Result: a 90-year extension added to the existing unexpired term, at zero peppercorn ground rent. The premium is calculated using a statutory formula based on ground rent, reversion value, and marriage value (below 80 years).
The statutory route protects the leaseholder: the freeholder cannot refuse (unless the property is a house rather than a flat, where different rules apply under the Leasehold Reform Act 1967), and the premium is set by agreement or, if not agreed, by the First-tier Tribunal (Property Chamber). The downside is the 2-year wait and the formal process.
2. Informal route (direct negotiation)
No ownership waiting period — a buyer can negotiate with the freeholder from the day of completion. The freeholder sets the price and the terms; the leaseholder does not have the statutory formula as a floor. An informal extension can be structured as any term and any ground rent the parties agree, which means the buyer must negotiate carefully to ensure the new lease is mortgageable and valuable.
At auction, some investors use the informal route to extend the lease quickly after purchase and then resell — the increase in value from extending a 65-year lease to 150 years can significantly exceed the premium paid, particularly where the vendor sets the price near the statutory formula.
When you buy a leasehold property at auction, the clock on the statutory 2-year wait starts from the date of your registration at Land Registry. During those 2 years, the lease continues to shorten. If the lease is already below 80 years, every month of additional shortening increases the marriage value element of the extension premium. Act quickly on informal negotiations if the lease is already short.
What drives the extension cost
The statutory extension premium has four main components:
- Capitalised ground rent — the present value of the ground rent the freeholder loses when the lease is extended to a peppercorn. Higher ground rent = higher premium.
- Deferment value (reversion) — the present value of the freeholder's right to regain the property at the end of the current lease term. Calculated using a deferment rate set by the Lands Tribunal (currently around 5% for flats).
- Marriage value — only where the unexpired term is below 80 years. The uplift in combined freehold and leasehold value created by the extension, of which 50% is paid to the freeholder.
- Freeholder's legal and surveyor costs — the leaseholder pays these on top of the premium; typically £1,000–£2,000 for the freeholder's solicitor and £500–£1,000 for the freeholder's RICS surveyor.
Indicative cost ranges by lease length
The figures below are illustrative guidance for a £250,000 flat with a modest ground rent. For accurate figures, use the Leasehold Advisory Service (LEASE) calculator. These figures should be treated as directional only — actual premiums depend heavily on ground rent, property value, location, and freeholder negotiating position.
| Unexpired Term | Indicative Premium | Marriage Value | Risk |
|---|---|---|---|
| 90+ years | £2,000 – £5,000 | None | Low |
| 85 years | £3,000 – £7,000 | None | Low |
| 80 years | £5,000 – £10,000 | Minimal / nil | Watch |
| 75 years | £7,000 – £16,000 | Applies | High |
| 70 years | £10,000 – £22,000 | Applies significantly | High |
| 65 years | £14,000 – £30,000 | Major component | Very High |
| 60 years | £20,000 – £40,000 | Dominant factor | Very High |
| 55 years | £28,000 – £55,000+ | Dominant factor | Extreme |
The figures above are for the extension premium only. Add £3,000–£6,000 for total professional fees: your solicitor (£1,500–£2,500), RICS surveyor (£500–£800), freeholder's solicitor (£1,000–£2,000, paid by you), and freeholder's surveyor (£500–£1,000, paid by you). Your total outlay is premium + fees.
Adding professional fees
A lease extension requires professional input on both sides. The leaseholder (you) pays for:
- Your own solicitor — to manage the Section 42 Notice, negotiate the premium and terms, and complete the extension deed. Fees: £1,500–£2,500
- Your own RICS surveyor — to value the property and calculate the correct extension premium. Fees: £500–£800
- The freeholder's solicitor — the leaseholder pays the reasonable legal costs of the freeholder's solicitor in dealing with the extension. Typically £1,000–£2,000
- The freeholder's surveyor — the leaseholder pays the reasonable surveyor costs of the freeholder. Typically £500–£1,000
- Land Registry registration fee — for registering the new extended lease. A few hundred pounds depending on the property value
Total professional fees: £3,500–£6,300 in addition to the extension premium.
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Analyse your legal pack — first analysis freeFrequently asked questions
How much does a lease extension cost in the UK?
Costs vary significantly by lease length, property value, ground rent, and whether marriage value applies. Indicative ranges for a £250,000 flat: 90 years: £2,000–£5,000; 80 years: £5,000–£10,000; 75 years: £7,000–£16,000; 65 years: £14,000–£30,000; 55 years: £28,000–£55,000+. Add £3,500–£6,000 for professional fees. Use the LEASE calculator for accurate figures on a specific property.
What is marriage value in lease extension?
Marriage value is the uplift in the combined value of the freehold and leasehold interests created by the extension. Below 80 years, the leaseholder must pay the freeholder 50% of this marriage value as part of the premium under the 1993 Act. This can add tens of thousands to the extension cost compared to a lease just above 80 years.
Can I extend a lease before I have owned the property for 2 years?
The statutory route requires 2 years' ownership before serving a Section 42 Notice. The informal route (direct negotiation with the freeholder) has no waiting period — you can negotiate from the day of completion. Most auction buyers either use the informal route immediately or factor the statutory route cost into their bid and wait 2 years.
What is the statutory lease extension process?
After 2 years' ownership, serve a Section 42 Notice on the freeholder stating the proposed premium. The freeholder has 2 months to counter-notice. If no agreement in 6 months of the counter-notice, either party applies to the First-tier Tribunal. The extension deed adds 90 years to the unexpired term and removes ground rent. The process typically takes 6–18 months if uncontested.
Should I extend the lease before or after buying?
At auction, you cannot extend before buying — you are not yet the leaseholder. Factor the full extension cost (premium + fees) into your maximum bid, complete the purchase, and then pursue the informal route immediately (no wait) or the statutory route after 2 years. If the lease is below 80 years, every month of delay increases the cost.
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