Lease extension cost: why the calculator, the freeholder's quote and the final bill all differ

A lease extension calculator estimates only the premium. A freeholder's quote is an opening offer on their own terms. The final bill is the agreed premium plus your solicitor, your valuer and, on the statutory route, the freeholder's reasonable costs as well. That's why a "£4-5k" calculator figure can turn into a five-figure total. Fees alone are budgeted at around £2,000 to £5,000 depending on the source (2026 guides).

Key takeaways

• The premium (the price paid to the freeholder) is only one part of the cost. Professional fees come on top.
• On the statutory route you also pay the freeholder's reasonable legal and valuation costs. HOA puts these at £1,400-£2,200 in its October 2026 example.
• An informal offer can look cheaper but may add fewer years, keep ground rent, or add new fees for selling, letting or keeping a pet.
• Calculators simplify. Most say they are not suitable for shared ownership.
• Ask for written, itemised quotes, and compare like with like: years added, ground rent and terms.

Why does my lease extension calculator say one thing and the freeholder another?

Because they're measuring different things.

Some real examples from forums. One owner of a 96-year lease on a £291k flat was told by a calculator "£4–£5k plus costs" (r/HousingUK snapshot). Another, with 88 years on a £500k flat, had an "estimated extension cost is £6.5k" and was told fees "can often add up to around £4k" (MSE forum, Dec 2025). A third posted that "the online calculators all say they are not suitable for shared ownership" (MSE forum).

What makes the premium vary:

• years left (above all whether you're under 80, when marriage value applies);
• the flat's value with and without the extension, which is often disputed;
• ground rent, and whether it doubles or is linked to an index;
• the deferment and capitalisation rates the valuers use (5% deferment is the current benchmark for flats, per LEASE);
• how well each side negotiates, and whether there are intermediate landlords or a head lease.

How much does a lease extension cost in total?

These are published fee ranges from two consumer guides updated in 2026. They are indicative only: real fees depend on the firm, the location, how complex the case is and whether it goes to tribunal. Ask for an itemised written quote.

The two guides give different totals. HOA's own line items add up to about £2,865-£4,465, so in practice the ranges overlap. Plan for the upper end if you live in London or if negotiations drag on.

Tribunal. If the two sides can't agree, either can apply to the First-tier Tribunal (Property Chamber) within six months of the freeholder's counter-notice (Osbornes Law). MSE mentions a wait of about four months for a hearing and says fees go up a lot, which is why it is "unusual to go this far".

Illustrative total. For a £500,000 flat with 85 years left, MSE's estimate is a £10,500 premium plus about £4,000 in professional fees, so about £14,500 in total. At 79 years, the same flat comes to about £34,500 (MSE). These are estimates, not valuations.

Do I have to pay the freeholder's costs?

On the statutory route, yes: you pay the freeholder's reasonable legal and valuation costs. At tribunal, HOA says both sides pay their own costs. As one forum reply put it: "If you have served a s42 notice then you are liable for the freeholders reasonable costs" (MSE forum). In that thread from 2019, the owner asked about a £990 valuer fee: "Surely £990 is excessive?" Costs can be challenged at the tribunal if they aren't reasonable. Ask your solicitor whether a challenge is worth it.

The 2024 reforms would make each side pay its own costs, with limited exceptions, but that isn't in force yet (LEASE). If you withdraw your notice, you still pay the freeholder's costs up to that date (Osbornes Law). Our decision guide shows what that can add up to.

Statutory or informal: which is cheaper?

It depends on what you get for the money, not just the headline price.

HOA warns that an informal extension "may appear at first to be cheaper and quicker" but "you could end up paying thousands more" (HOA). Some landlords won't negotiate informally at all. One forum reply about a housing association said it "will only do Statutory Lease extensions" (MSE forum, Feb 2026). An informal deal can still be fair. Just check it against what the statutory route would give you.

What clauses should I check in a freeholder's informal offer?

Go through this checklist with your solicitor before you accept anything:

• [ ] Total term after extension. How many years will you actually have? Is it enough for your lender and for future buyers?
• [ ] Ground rent. Will there be one? How much, and does it double or follow an index? Compare with the peppercorn on the statutory route.
• [ ] New or changed charges: fees for remortgaging, letting, selling, alterations or keeping pets.
• [ ] Other lease changes. Does the new lease change anything else, such as service charge or repair clauses?
• [ ] Price and validity. Is the figure fixed, and until what date? Get it in writing.
• [ ] Costs. Who pays the freeholder's legal and valuation fees? Is there a non-refundable quote fee?
• [ ] What happens if either side pulls out. Which costs are lost?
• [ ] Lender acceptance. Lending policies differ (Mortgage Solutions). Will your lender, or a buyer's lender, accept the new terms?
• [ ] Statutory benchmark. Has your own valuer priced the statutory route, so you can compare like with like?
• [ ] Timing against the 80-year mark. If you're close to 80, will the informal deal complete before you get there? If not, ask whether serving a Section 42 notice would protect your position.

FAQ

How much will it cost to extend my lease? That depends mainly on years left, flat value and ground rent. MSE's 2026 estimates range from £4,500 (a £200k flat at 90 years) to £30,500 (a £500k flat at 79 years) for the premium alone, plus about £4,000 in fees. Get a valuation from a chartered surveyor for a figure based on your own lease.

Why do lease extension calculators give such different figures? Each calculator uses its own simplified assumptions about rates, flat value and ground rent, and most leave out fees. They aren't designed for shared ownership or unusual leases. Use them as a rough starting point, not as a price.

Is the freeholder's valuer fee excessive? On the statutory route you only owe reasonable costs. HOA's October 2026 example puts the freeholder's valuer at £600-£900 and their solicitor at £800-£1,300. If a bill seems high, ask your solicitor whether to challenge it.

Is an informal lease extension cheaper? Sometimes the price is lower, but you may get fewer years, keep paying ground rent or take on new charges. Compare the total value of each deal, not only the price. Nothing is binding until signed.

Can the price go up after I buy the flat? On an informal basis, yes. A forum reply warned it "could rise… from £5k to £15k" or the freeholder could refuse. Since 31 January 2025 you can start the statutory route straight after buying.

Once a figure has been agreed with the freeholder, how long is it held for? That depends on what you've agreed. Get the figure, its expiry date and who pays which costs in writing. Your solicitor can tell you how long agreed terms bind both sides on the statutory route.

Next steps

Before you ask for quotes, write down your years left, ground rent terms, flat value evidence and the details of any informal offer. Our free Prepare a lease extension quote brief checklist helps you ask solicitors and valuers for comparable, itemised quotes. Then compare statutory and informal routes side by side.

Related: Lease extension solicitor fees: what a quote should include · What does a lease extension valuer do? · Leasehold reform tracker (October 2026)

Important: this is not legal or financial advice. Lease Extension Compass is independent, not a law firm, and doesn't recommend or rank providers. The fee ranges are indicative figures published in 2024-2026 and will vary with your circumstances. Ask for detailed written quotes and take advice from a qualified leasehold solicitor and an RICS-registered valuer.

Sources

1. Lease extension costs – HomeOwners Alliance (updated 22 Oct 2026)
2. Extend your lease – MoneySavingExpert (updated 17 Aug 2026)
3. Lease extension and leasehold reforms – LEASE (updated 27 Jan 2026)
4. Consultation on leasehold valuation rates – LEASE
5. What is a Section 42 notice? – Osbornes Law (updated 14 Aug 2026)
6. Extend now or wait? – Mortgage Solutions (9 Sept 2026)
7. r/HousingUK "Lease renewal" thread (snapshot)
8. "Extending a lease" – MSE forum (Dec 2025)
9. "Lease extension voluntary route" – MSE forum
10. "Extend your lease guide discussion", p77 – MSE forum (2019)
11. "Leasehold extension after purchase" – MSE forum (2023)
12. "Help with leasehold (complicated)" – MSE forum (Feb 2026)

General information, not legal advice. Rules and deadlines can change by jurisdiction. Check current laws and consult an appropriately qualified professional before acting.