Guide
With a leasehold flat you own the space, not the building or the ground under it. The years left on the lease matter more than almost anything else about the flat.
When you buy a leasehold flat you're buying the right to live there for a fixed number of years, not the bricks or the land. The freeholder owns those. That right is the lease, and how many years are left on it can matter more than the kitchen, the view or the postcode.
A lease starts long, often 99, 125 or 999 years, and counts down. While it's comfortably above 90 years, few people give it a thought. Below 80, it quietly becomes the biggest single thing affecting what the flat is worth and how easily it sells.
The reason is marriage value. Once a lease drops under 80 years, extending it gets a lot more expensive, because the law hands the freeholder a share of the value the extension adds. Cross that line and putting it right can cost thousands more than it would have a year earlier.
It gets worse further down. Under about 70 years, plenty of lenders won't offer a mortgage at all, which cuts your future buyers down to cash-only. That drags the price and can leave you stuck.
Leasehold is being overhauled, with recent law making extensions cheaper and a longer-term move to end it for new flats. That's good news, but don't buy on the promise of a change that hasn't fully arrived. Price the flat on the lease it has today, not the one it might have in a few years.