How to Extend Lease on Flat UK - A Practical Guide for Leaseholders

If you own a leasehold flat in the UK, extending the lease can protect the property's value, improve its mortgageability and make it easier to sell in the future. The process involves dealing with the freeholder, obtaining a valuation and agreeing the premium and legal terms.

For flats in England and Wales, there are currently formal and informal routes for extending a lease. The statutory route provides legal protections for qualifying leaseholders, while an informal extension is negotiated directly with the freeholder.

Check How Many Years Are Left

Start by checking your lease to establish the exact number of years remaining.

This is important because a short lease can become considerably more expensive to extend, particularly once it reaches 80 years or less under the current valuation rules.

You should also check:

• Current ground rent

• Ground rent review clauses

• Lease expiry date

• Freeholder details

• Any restrictions in the lease

• Existing service charge or management issues

Decide Between the Formal and Informal Routes

There are two main approaches.

Formal Lease Extension

The statutory route gives qualifying leaseholders a legal right to extend their flat lease.

Under the current statutory system, a qualifying flat leaseholder can generally obtain an additional 90 years, with the ground rent reduced to a peppercorn, meaning effectively zero financial ground rent.

The two-year ownership requirement was abolished in January 2025, so qualifying buyers no longer generally have to wait two years after purchasing a flat before starting a statutory lease extension claim.

Informal Lease Extension

The informal route involves negotiating directly with the freeholder.

It can sometimes be quicker and more flexible, but the freeholder does not have to agree to your proposal and may offer terms that are less favourable than the statutory route.

For this reason, you should understand the statutory position before accepting an informal offer.

Get a Professional Lease Valuation

Before serving a formal notice or agreeing a price with the freeholder, consider instructing a specialist lease extension valuer.

The valuation will consider factors such as:

• Property value

• Remaining lease term

• Ground rent

• Ground rent reviews

• Local property values

• Lease extension premium

• Whether the lease has 80 years or less remaining

The valuation is particularly important for a short lease because the premium can increase substantially as the lease gets shorter.

Instruct a Leasehold Solicitor

A solicitor experienced in lease extensions can handle the legal process and check that the necessary notices and documents are prepared correctly.

For a statutory extension, the formal process involves serving the appropriate notice on the freeholder. The freeholder then responds with a counter-notice setting out whether the claim is accepted and, where appropriate, its proposed terms and premium.

This is not an area where using the wrong notice or missing a statutory deadline is advisable.

Negotiate the Premium

Once the freeholder has responded, the two sides may negotiate the lease extension premium and other terms.

Your valuer and solicitor can negotiate on your behalf.

If the parties cannot agree, certain disputes can ultimately be determined by the First-tier Tribunal rather than leaving the leaseholder without a route forward.

Complete the New Lease

Once the premium and terms have been agreed, your solicitor will complete the legal documentation.

The new lease or lease variation then needs to be properly registered where required.

Keep copies of the completed documents, as they may be needed when you eventually sell or remortgage the flat.

How Much Does It Cost to Extend a Flat Lease?

There is no fixed UK price.

Your total cost can include:

• Lease extension premium

• Your valuer's fees

• Your solicitor's fees

• Freeholder-related costs where applicable under the current rules

• Land Registry fees

• Tribunal costs if a dispute occurs

• Other administrative expenses

The premium itself can be the largest expense, particularly for valuable flats with short leases.

What If Your Lease Has Less Than 80 Years?

A lease below 80 years deserves urgent attention under the current rules.

Under the existing statutory valuation framework, marriage value can increase the premium payable when a qualifying lease has 80 years or less remaining.

This can make delaying an extension expensive.

However, major leasehold reforms are being implemented. Proposed reforms include extending statutory leases to 990 years and removing marriage value, but these changes are not all currently in force.

Therefore, leaseholders should obtain current professional advice rather than assuming proposed reforms already apply to their situation.

Should You Extend the Lease Before Selling?

If you are planning to sell your flat, extending the lease can make the property more attractive to buyers.

A short lease may reduce the number of mortgage buyers interested in the property and give purchasers greater negotiating power.

Depending on your circumstances, you could:

• Extend the lease before marketing

• Begin the statutory process and sell with the claim progressing

• Sell the flat with the existing short lease

• Negotiate an informal extension with the freeholder

The most suitable strategy depends on the property's value, lease length, extension premium and how quickly you want to sell.

Extending a Lease on a London Flat

Lease extension issues are particularly relevant in London because of the large number of leasehold flats across areas such as Westminster, Kensington and Chelsea, Camden, Islington, Wandsworth and Southwark.

For a high-value London flat, even a relatively small change in the lease term can have a substantial effect on the property's marketability and extension premium.

Getting the lease assessed before making an offer or putting the property on the market can therefore be commercially important.

How Fraser Bond Can Help

Fraser Bond can assist leaseholders, buyers, sellers and investors in understanding the property implications of short leases and lease extensions.

Whether you are extending a lease before selling, buying a flat with a short lease or assessing the investment potential of a leasehold property, understanding the remaining term and likely extension costs can help you make a better-informed decision.