Marriage value is the most misunderstood, expensive part of a lease extension premium for short leases. Learn how it's calculated and when it's abolished.
Marriage value is the part of a lease extension premium that most often surprises leaseholders, because it does not exist at all until your lease has 80 years or fewer left, and then it can become the largest single component. The rest of this guide explains what it is, how it is measured, how big it gets, and what the law says about abolishing it.
A short lease and the freehold are worth less separately than a long lease would be. When you extend, the two interests are effectively “married”: your lease becomes long, the freeholder's interest shrinks to a distant reversion, and the combined value of the two goes up. Marriage value is that increase, and under Schedule 13 to the 1993 Act the freeholder is entitled to 50% of it, with the leaseholder keeping the other half.
It is payable only where the unexpired term at the valuation date is 80 years or fewer. The valuation date is the date your section 42 notice is served, not the date the extension completes. That is why a lease at 81 years pays no marriage value at all while the same lease at 80 years pays about £10,000 on a £400,000 flat (see the table below).
Marriage value is the reason an extension costing about £11,500 with 81 years remaining could cost about £22,000–£23,000 with 80 or 79 years remaining — for the same property and the same transaction.
Marriage value = (extended lease value + freeholder's interest after extension) − (current lease value + capitalised ground rent + freeholder's current reversion)
The freeholder receives half of that figure. To value the current lease you need a relativity: the percentage of the freehold value that a lease of that length is worth. We use the Gerald Eve 2016 table (about 86% at 72 years, 70.5% at 50 years). The extended lease (existing term plus 90 years) is valued at about 98–98.5% of freehold value. See our guide to relativity tables for how these are used and disputed.
Property freehold value: £400,000 | Unexpired lease: 72 years | Ground rent: £200/yr
Same method and inputs as our calculator, at 5% rates. A surveyor may use different rates or relativity evidence.
For a £400,000 flat with £200 ground rent, our calculator gives:
| Years left | Marriage value | Total premium |
|---|---|---|
| 81 | £0 | about £11,500 |
| 80 | about £10,100 | about £21,900 |
| 75 | about £14,200 | about £28,300 |
| 70 | about £18,700 | about £35,600 |
| 60 | about £28,100 | about £53,000 |
| 50 | about £37,000 | about £75,100 |
| 40 | about £43,200 | about £102,700 |
Two things stand out. First, the jump at the 80-year line is abrupt, which is why timing the notice matters (see below). Second, marriage value alone does not explain the rising cost: the reversion grows too as the lease shortens, so the whole premium accelerates. Figures scale with property value, so a £800,000 flat will cost roughly double.
Marriage value is very sensitive to the relativity used for the current lease, because it is the biggest input to the existing lease value. On the 72-year example above, a relativity of 83.1% instead of 86.1% would push marriage value up from about £17,000 to about £23,000, while 89.1% would bring it down to about £11,000. Freeholders' surveyors tend to argue for lower relativities, leaseholders' for higher ones. Since Sloane Stanley Estate v Mundy (2016), tribunals have preferred real-world evidence of comparable sales to rely on graphs alone, so a valuer with current evidence is worth paying for. See also how the premium is calculated.
The Leasehold and Freehold Reform Act 2024 provides for marriage value to be abolished for residential lease extensions and enfranchisement, but that provision is not yet in force and there is no confirmed commencement date. Commencement depends on the government setting the new valuation rules by regulations, and the government has been consulting on the valuation rates (the consultation closes on 21 October 2026). Until the relevant provisions are commenced, marriage value is payable under the current rules.
If abolition is implemented, a leaseholder with a 70-year lease on a £400,000 flat would save about £18,700 of marriage value on our calculator's figures. But no date is confirmed, and every year you wait the reversion (and, if you cross below 80, the marriage value) goes up, which can cancel out the saving. Do not rely on reform arriving in time; get specialist advice before deciding. See Should I wait or extend now?
Marriage value is the increase in the combined value of the leaseholder's and freeholder's interests when a short lease is extended. Under Schedule 13 to the 1993 Act, the freeholder is entitled to 50% of that increase. It is only payable where the unexpired term at the valuation date is 80 years or fewer.
When the unexpired term is 80 years or fewer on the date your section 42 notice is served. Above 80 years there is none. On a £400,000 flat with £200 ground rent our calculator shows no marriage value at 81 years and about £10,100 at 80 years, which is why serving the notice before the lease falls to 80 years can save a large sum.
It depends on the property value, the lease length and the relativity applied. For a £400,000 flat our calculator gives about £14,200 at 75 years, £18,700 at 70 years and £28,100 at 60 years. It scales roughly with the value of the flat. A surveyor's valuation can differ because of the relativity evidence they use.
The 2024 Act provides for it, but the provision is not yet in force and no commencement date has been confirmed. The government has been consulting on valuation rates, and the consultation closes on 21 October 2026. Until the provisions are commenced, marriage value remains payable. Do not assume it will be abolished before you need to extend.
The notice date. The lease length used for the premium, and for deciding whether marriage value applies, is the unexpired term on the date you serve your section 42 notice, not the date the extension completes. A lease that drops below 80 years during the process does not make the premium higher.
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This guide is researched from official and primary sources. Check them directly before relying on any figure or date.
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