What should you check before buying a leasehold flat in London?

Most flats in London are leasehold, which means that when you buy one, you are not purchasing the building outright but rather the right to occupy it for a defined period of time, subject to the terms of a lease that was often written decades before you arrived on the scene.

For most buyers, this is their first encounter with a set of legal concepts that simply do not apply to buying a freehold house, and the risks that come with them, from a lease that is too short to mortgage to a service charge that is about to spike, are not always visible from the listing or the sales brochure.

The time to identify these issues is before you exchange, not after. This guide covers the key things to check when buying a leasehold flat in London, why they matter, and what your solicitor should be doing to protect you throughout the process.

What is the difference between freehold and leasehold?

Understanding the difference between freehold and leasehold is the starting point for everything that follows. When you buy a freehold property, you own the building and the land it sits on outright, with no time limit on your ownership, no landlord above you, and no lease to comply with. Most houses in England and Wales are sold on this basis.

What is a leasehold property?

When you buy leasehold, you are purchasing a long-term tenancy rather than outright ownership. The lease grants you the right to occupy the property for a specified number of years, originally perhaps 99, 125, or 999 years, but the freehold of the building remains with a separate party known as the freeholder or landlord. In practice, freehold vs leasehold for a London flat buyer means you will have ongoing obligations to the freeholder throughout your ownership:

• You will pay a service charge to cover the maintenance and management of the building
• You may pay ground rent
• You will need to comply with the terms of the lease, which can include restrictions on how you use, alter, or decorate the property

The lease is the document that governs all of this, and your solicitor's job is to read it in full, understand it, and make sure you do too before you commit to buying.

What does your solicitor check on a leasehold property in London?

Leasehold conveyancing involves significantly more work than a freehold purchase at the same value. The table below summarises the key areas your solicitor will check and why each one matters.

Each of these areas can affect the value, mortgageability, and long-term ownership of the property. The sections below cover the most important ones in more detail.

Lease length and the 80-year threshold

The remaining term on the lease is one of the most important numbers in the entire transaction. Most mortgage lenders require a minimum lease length at the point of completion, and many require a significant buffer above that minimum to account for the years you intend to own the property.

The 80-year lease rule is the critical threshold. Once a lease falls below 80 years, the cost of extending it increases significantly because of a concept called marriage value. Marriage value is the additional value created when a short lease is extended, and under current legislation the freeholder is entitled to 50% of it once the lease drops below 80 years.

The Leasehold and Freehold Reform Act 2024 provides for marriage value to be abolished, but as of 2026 this change has not yet been brought into force, so the existing rules continue to apply.

On a London flat where property values are high, this can add tens of thousands of pounds to the cost of an extension. For a buyer, a lease with fewer than 80 years remaining is a serious red flag that will limit your mortgage options, increase your extension costs, and make the property harder to sell in the future.

What is ground rent?

It is an annual charge payable to the freeholder under the terms of the lease. Historically ground rents were a nominal amount, but in more recent decades some developers introduced ground rent clauses that escalate significantly over time, either doubling at set intervals or increasing in line with RPI.

The Leasehold Reform (Ground Rent) Act 2022 banned the charging of ground rent above a peppercorn amount on new residential leases, but it does not apply retrospectively to existing leases. If the property you are buying has a ground rent clause that escalates, your solicitor should identify this and explain its implications before you exchange.

Service charges and the reserve fund

The service charge on a leasehold property covers the cost of maintaining and managing the building. Your solicitor will request three years of service charge accounts as part of the leasehold enquiries, which show what has been charged historically and whether the building has been properly maintained.

They will also check the reserve fund, which is the pot of money set aside for major future works such as roof replacement or external redecoration. A low reserve fund on a building that clearly needs significant work is a warning sign, as it can mean a large one-off demand arriving shortly after you complete.

How much does a lease extension cost and when should you think about it?

If the lease on the property you are buying has fewer than around 90 years remaining, thinking about a lease extension before or shortly after purchase is worth doing. How much does a lease extension cost? The total cost depends on three main factors:

• The remaining lease length
• The value of the property
• The ground rent terms in the existing lease

There are two main cost components: the premium paid to the freeholder, calculated using a statutory formula for qualifying leaseholders, and the legal and valuation fees on both sides of the negotiation.

On a London flat with a lease of around 85 years remaining, a lease extension premium can range from a few thousand to tens of thousands of pounds depending on the property value. Once the lease falls below 80 years, marriage value is added into the calculation and the premium increases substantially.

Lease extension solicitors in London can handle both the statutory lease extension process and informal negotiations with the freeholder. The previous requirement to own a property for two years before making a statutory lease extension claim was removed in January 2025, meaning qualifying leaseholders can now begin the process without waiting two years.

If the lease is already short and you are buying with a mortgage, your lender may require you to arrange the extension as a condition of the mortgage offer.

What happens when a lease runs out?

In practice, leases very rarely reach their expiry date because leaseholders have the right to extend well before that point. However, as a lease approaches the lower end of the range, below 70 years in particular, it becomes progressively harder to mortgage and harder to sell, which is why addressing a short lease early removes that risk before it becomes a problem.

Which lenders have restrictions on short leases?

Lender requirements on minimum lease length vary, but most major lenders require at least 70 years remaining at the point of completion, with many requiring significantly more.

There is no single minimum lease length that applies across all mortgage lenders. Each lender sets its own criteria, which may specify a minimum number of years remaining at completion or a required number of years remaining at the end of the mortgage term. This means a lease that is acceptable to one lender may not meet the requirements of another.

The lenders most commonly encountered in the London flat market each have their own minimum lease requirements. Lloyds Bank, Barclays, NatWest, HSBC, Nationwide, and Halifax all apply minimum lease length criteria, and your solicitor will confirm whether the lease meets your lender's specific requirements as part of the standard reporting process.

Common leasehold problems to look out for in London

Beyond the headline checks above, several leasehold problems come up with particular frequency in London transactions.

Absent freeholders are one of the more disruptive issues. If the freeholder cannot be traced, obtaining consent for alterations, subletting, or a lease extension becomes difficult, and your solicitor may recommend indemnity insurance to cover the risk of the freeholder appearing and asserting their rights.

Poorly maintained communal areas can signal broader management problems that will become your responsibility after completion. Your solicitor's review of the service charge accounts should reveal whether maintenance has been consistently funded or repeatedly deferred, which is often an early indicator of a building that is not being managed well.

Unlicensed alterations are common in older London conversions where previous owners have extended into loft space, combined rooms, or made structural changes without obtaining the necessary freeholder consent.

Your solicitor should raise enquiries about any alterations and check whether the appropriate licences or retrospective approvals are in place. Where they are not, indemnity insurance or outstanding planning permission queries may need to be resolved before exchange.

How much does leasehold conveyancing cost in London?

Leasehold conveyancing costs are higher than for a freehold purchase of equivalent value, reflecting the additional work involved. The legal fee is typically higher to account for the extended enquiries, and the leasehold disbursements include additional items that do not arise on a freehold purchase.

On a leasehold purchase you will typically see the following additional disbursements:

• Notice of transfer fee, paid to the freeholder to notify them of the change of ownership
• Notice of charge fee if you have a mortgage, notifying the freeholder of the lender's interest
• Deed of covenant fee where the lease requires the buyer to enter into a direct covenant with the freeholder
• Certificate of compliance fee in some developments

These charges are set by the freeholder or management company rather than by your solicitor and vary from building to building. Your solicitor should identify and quantify them from the leasehold information pack before you exchange, so you know the full cost in advance.

You can see the typical conveyancing fees for buyers as a baseline, and the additional disbursements guide covers each leasehold item in detail. For London-specific fee estimates, the London conveyancing calculator gives you an accurate picture based on your property value and transaction type.

The full leasehold conveyancing guide covers the process in more detail if you want a deeper understanding of what is involved before you instruct anyone.

Ready to get a leasehold conveyancing quote for your London property?

Buying a leasehold flat in London is manageable with the right solicitor and the right preparation. The checks outlined above are exactly what an experienced leasehold conveyancer should be carrying out as a matter of course, and your job is to make sure you understand what they find and what it means for your purchase before you commit.

Find a solicitor experienced in London leasehold conveyancing and compare leasehold conveyancing quotes today.