Marriage Value for Leaseholds: What UK Leaseholders Need to Know

If you own a leasehold flat in the UK and your lease is approaching — or has already dropped below — 80 years, marriage value is one of the most important financial concepts you need to understand. It can add thousands of pounds to the cost of extending your lease and directly affects the value of your home. This guide explains what marriage value is, how it is calculated, and what upcoming reforms could mean for you.

What Is Marriage Value?

Marriage value is the increase in a property's overall value that occurs when a short lease is merged with the freehold interest to create a longer lease. The term comes from the idea that bringing two separate interests together — "marrying" them — produces a combined value greater than the sum of the parts.

Under the Leasehold Reform, Housing and Urban Development Act 1993, when a leaseholder extends their lease, the freeholder is entitled to receive 50% of the marriage value as part of the premium. This only applies when the lease has fewer than 80 years remaining.

In practical terms, marriage value reflects the fact that a flat with a long lease is worth significantly more than one with a short lease. When the lease is extended, this value gap closes, and the freeholder is compensated for their share of the uplift.

Why Does the 80-Year Threshold Matter?

The 80-year mark is a critical boundary in leasehold law. Above 80 years, the 1993 Act treats marriage value as zero — so it does not feature in the premium calculation at all. Once the lease drops below 80 years, the leaseholder must pay 50% of the marriage value on top of the other components of the premium.

This creates what many describe as a financial cliff edge. A leaseholder with 81 years remaining pays no marriage value, while a leaseholder with 79 years remaining could face an additional bill of tens of thousands of pounds. The shorter the lease, the larger the marriage value becomes, because the gap between the short-lease value and the extended-lease value widens.

How the 80-Year Rule Affects Costs

To illustrate the impact, consider a flat worth £300,000 with an extended lease:

• 90 years remaining: No marriage value applies. The premium consists only of the capitalised ground rent and the freeholder's reversion. Typical cost: £5,000–£12,000.
• 75 years remaining: Marriage value applies. The premium increases significantly. Typical cost: £15,000–£25,000.
• 60 years remaining: Marriage value is substantial. Typical cost: £30,000–£50,000 or more.

These figures are illustrative — actual costs depend on the specific property, ground rent, and professional valuations. You can use our lease extension calculator for a personalised estimate.

How Is Marriage Value Calculated?

The calculation of marriage value follows a specific formula set out in Schedule 13 of the 1993 Act. In simplified terms:

The Formula

Marriage value is the difference between the combined value of the interests after the extension and the combined value before the extension:

• Value after extension = value of the new extended lease + freeholder's improved interest (the peppercorn ground rent reversion)
• Value before extension = value of the existing short lease + freeholder's current interest (capitalised ground rent + reversion)
• Marriage value = (value after) − (value before)
• Leaseholder's share = 50% of the marriage value

Key Valuation Inputs

Several factors feed into the calculation:

• Current property value — the market value of the flat with the existing short lease.
• Extended lease value — the estimated value of the flat with a new 990-year lease at a peppercorn rent (effectively no ground rent).
• Relativity — the ratio of the short lease value to the long lease value. Published relativity graphs from firms like Gerald Eve, Savills, and John D. Wood are commonly used to establish this figure.
• Deferment rate — set at 5% for flats following the Sportelli decision (2006) in the House of Lords.
• Capitalisation rate — typically 6–7% for residential ground rents, used to calculate the present value of the ground rent income stream the freeholder will lose.

A Worked Example

Suppose a flat has an extended lease value of £300,000, a current short lease value of £210,000 (relativity of 70%), and the freeholder's existing interest is valued at £50,000:

• Value after extension: £300,000 (extended lease) + £0 (freeholder's residual interest after granting a 990-year extension is negligible) = £300,000
• Value before extension: £210,000 (short lease) + £50,000 (freeholder's interest) = £260,000
• Marriage value: £300,000 − £260,000 = £40,000
• Leaseholder's share (50%): £20,000

This £20,000 is added to the other premium components (capitalised ground rent and the reversion), forming part of the total cost of extending.

Components of the Lease Extension Premium

Marriage value is only one part of the total premium a leaseholder pays to extend. The full statutory premium under the 1993 Act consists of three elements:

• Capitalised ground rent — the present value of the ground rent the freeholder will no longer receive. This is calculated by discounting the remaining ground rent payments at the capitalisation rate.
• Reversion — the present value of the freeholder's right to regain possession of the property when the lease expires. This is calculated using the deferment rate.
• Marriage value (if applicable) — 50% of the increase in the property's overall value resulting from the extension, payable only when the lease is below 80 years.

For leases above 80 years, only the first two elements apply, which is why extending earlier is almost always cheaper. Below 80 years, marriage value typically becomes the largest single component of the premium, as confirmed by the RICS guidance on leasehold enfranchisement valuations.

Marriage Value and Property Value

Marriage value does not just affect the cost of extending — it also reflects the impact a short lease has on your property's market value. Buyers and mortgage lenders pay close attention to the remaining lease term:

• Below 80 years: Many buyers will discount their offer to account for the cost of extending, including marriage value. Some may walk away entirely.
• Below 70 years: Most mortgage lenders will not offer a loan on a lease this short, making the property effectively cash-buyer only and significantly reducing its market value.
• Below 60 years: The property becomes very difficult to sell. Marriage value by this point could represent 30–50% of the total premium, and the flat's market value may be 40–50% below what it would be worth with a long lease.

This is why extending your lease before it drops below 80 years is one of the most valuable financial decisions a leaseholder can make. The cost difference either side of the threshold can be dramatic.

The Leasehold and Freehold Reform Act 2024

The Leasehold and Freehold Reform Act 2024 received Royal Assent in May 2024 and includes provisions to abolish marriage value entirely. Once commenced, leaseholders extending a lease below 80 years will no longer have to pay the freeholder 50% of the uplift in value.

What the 2024 Act Changes

The key reform relevant to marriage value is straightforward: the Act removes the concept from the premium calculation altogether. When the relevant provisions come into force, the premium for extending will consist only of the capitalised ground rent and the reversion — regardless of the remaining lease length.

The government has also indicated that a new standardised valuation framework will accompany the changes, including prescribed rates to replace the current reliance on tribunal precedent and negotiation. Further details are expected in secondary legislation.

When Will the Changes Take Effect?

As of early 2026, the marriage value abolition provisions have not yet been commenced. The government needs to finalise the secondary legislation that will set out the new valuation methodology, prescribed rates, and transitional arrangements.

No official commencement date has been confirmed. Some industry commentators expect the new regime to take effect in 2026 or 2027, but leasehold reform has a history of delays, and the technical complexity of the new framework means further postponement is possible.

For a detailed discussion of whether to wait for the reforms or extend now, read our guide: Should I Wait for Marriage Value to Be Abolished Before Extending My Lease?

Strategies to Minimise Marriage Value

While you cannot avoid marriage value if your lease is already below 80 years, there are practical steps to manage and minimise it:

Extend Before the 80-Year Threshold

The single most effective strategy is to extend your lease while it still has more than 80 years remaining. This eliminates marriage value from the calculation entirely and keeps the premium significantly lower.

Serve a Section 42 Notice Early

If your lease is already below 80 years, serving a Section 42 notice fixes the valuation date. This stops the clock on your lease getting shorter for the purposes of the premium calculation, preventing marriage value from increasing further while you negotiate or wait for reforms.

Get a Professional Valuation

Marriage value calculations involve professional judgment, particularly around relativity. An experienced leasehold valuer can ensure the calculation uses appropriate figures and identify where the freeholder may be overstating the marriage value element.

Consider the Tribunal

If you cannot agree on the premium with your freeholder, you can apply to the First-tier Tribunal (Property Chamber) for a determination. The tribunal will set the premium based on the evidence, and its decisions on marriage value can sometimes be lower than the freeholder's initial demands.

Frequently Asked Questions

The Bottom Line

Marriage value is one of the most significant costs facing leaseholders with a lease below 80 years. It can add tens of thousands of pounds to a lease extension premium and is the primary reason extending becomes dramatically more expensive once you cross the 80-year threshold.

The upcoming abolition of marriage value under the Leasehold and Freehold Reform Act 2024 will be a major benefit for leaseholders — but until the provisions are formally commenced, the current rules remain in force. If your lease is approaching 80 years, the most prudent course of action is to extend now rather than wait for reforms with no confirmed timetable.

Whether you decide to extend immediately or hold off, understanding how marriage value works puts you in a stronger position to make an informed decision about your home and your finances.