Test whether your block qualifies and estimate the price and each flat’s share.
Flat owners buy the freehold of the whole building together. Enter the building, test the eligibility rules and estimate the price using the statutory method.
This is an estimate of the freehold price only. It leaves out any non-residential parts, development or hope value, and the freeholder’s other interests, which a valuer must add. The equal split per flat is a starting point; participants usually agree a split by flat value or floor area.
Under the Leasehold Reform, Housing and Urban Development Act 1993, qualifying flat owners can buy the freehold of their building together. The price is not the sum of separate lease extensions. It is the value of the freeholder’s interest in the whole building: the ground rents of every flat, the reversion of every flat, and a share of the marriage value for participating flats that have 80 years or fewer left.
The calculator uses the same method as our lease extension calculator: ground rent capitalised at 5%, reversion at 5% (the value of the flat at the end of its lease less its value after a 90-year extension), the Gerald Eve 2016 relativity graph, and 50% of the marriage value. It works from an average flat, so tell it how many flats are in a short-lease group and how many of those are joining. A real valuation looks at each flat separately.
It also tests the eligibility rules. The building must have at least two flats, at least two-thirds of the flats must be held by qualifying tenants on long leases, the participating flats must be at least half of the building, and no more than 25% of the floor area can be non-residential. The right to manage limit of 50% is shown beside it so a mixed-use block can see which route fits.
These examples use the calculator’s method with equal flat values, 5% rates and no costs.
| Building | Capitalised ground rent | Reversion | Marriage value | Total | Per participating flat |
|---|---|---|---|---|---|
| 6 flats, 4 join; all flats 95 years, £350,000, ground rent £150 | £17,825 | £20,129 | £0 | £37,954 | £9,489 |
| 6 flats, 4 join; 2 flats at 72 years join, rest 95 years, £350,000, ground rent £150 | £17,705 | £34,028 | £30,166 | £81,899 | £20,475 |
| 10 flats, 6 join; 3 flats at 76 years (2 join), rest 110 years, £500,000, ground rent £250 | £49,469 | £52,470 | £33,518 | £135,456 | £22,576 |
| Test | Collective enfranchisement | Right to manage |
|---|---|---|
| Minimum flats | At least two flats in a self-contained building | At least two flats |
| Qualifying tenants | At least two-thirds of the flats held by qualifying tenants on long leases | At least two-thirds of the flats held by qualifying tenants |
| Participation | Participating flats at least half of all flats | At least half of the qualifying tenants must take part |
| Non-residential floor area | No more than 25% (the 50% limit in the 2024 Act has not been brought into force for collective enfranchisement) | No more than 50% since 3 March 2025 |
| Result | You buy the freehold | You take over management; the freehold stays with the landlord |
| Component | What it is | Who it applies to |
|---|---|---|
| Capitalised ground rent | Value of the ground rents over the remaining terms, at 5% | Every flat in the building |
| Reversion | Value of getting each flat back at the end of its lease, less the value after a 90-year extension | Every flat in the building |
| Marriage value | 50% of the gain in value from extending each short lease; only where 80 years or fewer remain | Participating flats at 80 years or fewer |
| Not included | Non-residential parts, development or hope value, the freeholder’s other interests, costs, SDLT | Get a valuer to add these |
Sources
Related guides
It is the right of flat owners to buy the freehold of their building together, through a nominated purchaser such as a company the participants own. The price is a statutory valuation of the whole building, not the sum of separate lease extension premiums.
Qualifying tenants of at least half of the flats in the building must take part, and at least two-thirds of all the flats must be held by qualifying tenants on long leases. In a building of two flats, both must join. Check the current rules with a solicitor before serving notice.
No more than 25% of the internal floor area of the building can be non-residential for a collective enfranchisement claim. The right to manage limit is 50% since 3 March 2025, and the 2024 Act provides for 50% for enfranchisement too, but that change has not been brought into force. The calculator tests both so you can see which route a mixed-use block fits.
Yes, where a participating flat has 80 years or fewer left. Marriage value is 50% of the gain in value from granting that flat a longer lease. The 2024 Act would abolish it, but that provision is not in force.
No. You enter your own quotes. Participants normally pay the freeholder’s reasonable costs as well as their own, and the purchase can attract stamp duty, so use real figures from a solicitor and valuer.
Yes. The price covers the freeholder’s interest in the whole building, including the ground rents and reversions of flats that do not take part, so every flat counts in the ground rent and reversion lines. Marriage value only counts for participating flats.
This calculator was built and is maintained by Rahul Tandon, an independent web developer and researcher. It applies published statutory rules and the 5% Sportelli deferment rate, and every assumption is shown on this page. The formulas and limits are on the methodology page; see our editorial policy. LeaseVault is not a law firm, a surveying practice or a mortgage broker, and the result is an estimate for initial budgeting, not legal, financial or valuation advice.
We’ll notify you when 2024 Act provisions come into force and when new premium rates are confirmed.