Extending a lease can feel overwhelming, whether you’re a homeowner living in the property or an investor managing a portfolio. However, understanding the key stages and considerations can make the process far more manageable and help you avoid costly mistakes.

Below are some of the most important factors to consider when navigating a lease extension.

1. Understanding the 80-Year Threshold and Marriage Value

One of the most critical points in any lease is the 80-year mark. Once a lease drops below 80 years, it is classed as a short lease, and something known as marriage value becomes payable.

At this stage, the value of the flat can begin to reduce, and the cost of extending the lease increases significantly. Acting before the lease falls below this threshold can protect both the property’s value and your future negotiating position.

2. Requesting a Quote from the Freeholder

The first practical step is to obtain a lease extension quote from the freeholder.

This can be done:

• Directly by you as the property owner, or

• Through your solicitor acting on your behalf

Having professional representation at this stage can help ensure the quote is realistic and that your position is properly protected from the outset.

3. The Two Routes to Extending a Lease

There are two main routes available when extending a lease:

Voluntary (Informal) Route

This route allows more flexibility in terms of the lease length, which could be 99, 125, or even 999 years. In many cases, the extended portion of the lease comes with zero ground rent. While this route can be quicker, the terms are negotiated directly with the freeholder.

Statutory Section 42 Route

Under this formal legal route, 90 years are added to the existing lease, and the ground rent is reduced to a peppercorn (effectively zero). This route offers more protection, as the freeholder cannot refuse the extension if the legal criteria are met.

4. Costs to Budget For

Lease extensions involve more than just the premium paid to the freeholder. The leaseholder is also responsible for:

• The freeholder’s legal fees

• Their own legal fees

• Valuation and surveyor costs

Understanding these additional expenses early on helps avoid unexpected costs later in the process.

5. The Importance of Reliability and Reputation

In property, reputation matters.

Investors and homeowners who consistently complete transactions as agreed build trust with freeholders, agents, solicitors, and lenders. This reliability often leads to smoother negotiations and, in some cases, more favourable terms — particularly where speed and certainty are valued.

Over time, this track record becomes a real asset.

6. Dealing with Difficult Freeholders

If a freeholder proves uncooperative through the voluntary route, the Section 42 statutory process provides a solution.

Once a valid Section 42 notice is served, the freeholder cannot refuse to engage in the lease extension process. This route exists specifically to protect leaseholders when negotiations become challenging.

7. Agreeing the Premium and Time Limits

Once a premium has been agreed with the freeholder, the lease extension must be completed within three months.

If this deadline is missed, the freeholder is entitled to withdraw the offer and restart the process, meaning the original quote may no longer apply.

8. When a Premium Cannot Be Agreed

If negotiations under the Section 42 route fail and no agreement is reached after six months, the matter can be referred to a tribunal.

The tribunal will determine the premium payable based on valuation reports and supporting evidence from both sides.

9. How Lease Extension Premiums Are Calculated

There is a single lease extension premium formula, but it contains multiple variables.

These can include:

• Deferment rate

• Capitalisation rate

• Marriage value

• Current and future value of the flat

• Loss of ground rent

Because of these variables, professional valuation advice is essential to ensure the premium is fair and accurate.

10. Leasehold and Commonhold Reform Bill

The draft Leasehold and Commonhold Reform Bill was released in January 2026. Labour has indicated that this will move through Parliament for debate, with decisions expected by late 2028.

Proposed changes include:

• Potential removal or reform of marriage value

• Lease extensions of 990 years instead of 90 years

• Further changes to ground rent structures

These reforms could significantly reshape the lease extension landscape in the coming years.