Mortgage terms and extending your mortgage term

A mortgage term is the number of years over which you agree to repay the loan. Most lenders offer terms of 25 to 30 years as standard, but terms can be shorter or longer, and the term you choose shapes two things at once: how much you pay each month and how much interest you pay in total¹. Stretch the term out and the monthly payment falls, because the same balance is spread across more payments. But interest is charged for every month the debt exists, so the total cost of the mortgage rises².

Because a mortgage is a loan secured against your home, the lender keeps a charge over the property until it is repaid, and if repayments stop the lender can repossess, normally with a court order³. That is why the term matters beyond the monthly figure: it sets the date the debt must be gone by, and lenders look hard at whether you can realistically afford the payments for the whole term, including into later life.

What a mortgage term is and how long it usually runs

The term is set when the mortgage is taken out, and it ends on a fixed date when the final payment is due. Lenders offer different terms, usually 25 to 30 years¹. A repayment mortgage clears both interest and a slice of the balance each month, so by the end of the term the debt is gone. An interest-only mortgage pays just the interest, and the whole loan has to be repaid at the end of the term in one lump⁷.

The term is separate from any deal period. A fixed rate might last two or five years and then revert to the lender's standard variable rate, but the term runs on underneath, unchanged, until the mortgage is paid off or you ask to change it. When a deal ends you can switch to a new deal with your lender or remortgage, and either route can also be the moment to change the term.

Terms have crept longer over the years because house prices have risen faster than incomes. First-time buyers in particular have used longer terms to bring monthly payments within reach, with 35-year terms a recognised route to lower repayments⁴. A longer term at the outset is a choice made when you apply; extending a term later, part-way through a mortgage, is a separate process and is what the rest of this page is about.

A longer term lowers payments but raises the total cost

The trade-off is simple and unavoidable. Extending the term lowers your monthly payments, making them more affordable, but you pay more interest overall². The same principle applies to any borrowing spread over more time: the payments look smaller, but interest is charged for the whole period the money is owed⁹. Shelter makes the same point about term extensions and interest-only switches used as ways to cut payments: they reduce the monthly cost now, but cost more over the lifetime of the mortgage¹⁰.

The size of the effect depends on the balance and the rate, not on any rule of thumb: the more years added, the more months of interest. It also depends on what you do next. If you later overpay or shorten the term again, some of that extra interest can be avoided, though an early repayment charge may apply during a fixed rate period.

A term extension is not the only way to reduce payments, and the alternatives carry the same trade-off in different forms. Lenders may reduce payments for a set period, charge interest only for a while on a repayment mortgage, give a payment holiday, or extend the term¹². A payment holiday, for instance, only pauses the problem: you still have to pay off the whole mortgage afterwards, either by increasing your monthly payments or by extending the term¹³. Whichever route is used, the debt still has to clear eventually, and pushing the end date back is what makes the whole thing cost more.

Who can extend: lender criteria and age limits

Whether a lender agrees to extend a term is a decision, not a right, and it depends on what the lender can see about your situation. The likelihood of agreement usually depends on factors such as how large your arrears are, your age and expected retirement date, whether you have a permanent job, and the remaining term¹⁴. A borrower who is up to date, in work and years from retirement will find it much easier than one who is already behind.

Age is the criterion that most often blocks an extension. Lenders consider your age at application and the age you will be at the end of the mortgage, and many have an upper age cap beyond which they will not lend¹⁵. The same limit affects family-assisted mortgages: lenders tend only to offer mortgages that run to age 70 or 75, so older parents can struggle to be approved¹⁶.

There is also a regulatory backdrop. When a mortgage is varied, the rules allow more change than many borrowers expect: a remortgage with the same or a different lender does not have to be exactly like-for-like, and the borrower can, for example, extend the term, move from interest-only to repayment, or change the interest rate type¹⁷. So extending a term is a normal, permitted variation, but the lender still has to be satisfied it is affordable for the whole new term, and that is where age and income come in.

Maximum term: 35 or 40 years, within an age limit

The ceiling on term length comes from two directions: the maximum term a lender will offer, and the maximum age they will lend to. Most lenders offer maximum mortgage terms of 35 or even 40 years, but they may not be on offer to everyone⁴. Age limits of 75 and 80 at the end of the mortgage are common, so a borrower over 40 may find their options limited when a 40-year term would run past the cap⁴. Similar limits appear across the market: let-to-buy mortgages typically set a maximum age of 70 or 75⁵.

In practice the two limits work together. A 30-year-old could in principle take a 40-year term and still finish before 75; a 50-year-old cannot, and will be offered a shorter term with higher monthly payments, or pointed towards products designed for later life. When an existing mortgage is being extended rather than set up fresh, the same caps apply: many lenders will not extend a mortgage beyond 25 to 30 years¹⁴.

If the term cannot be extended far enough to make payments affordable, the alternatives narrow. Later-life options include retirement interest-only mortgages, where the capital is repaid when the home is sold or on death, and equity release, where lifetime mortgages generally require the borrower to be at least 55¹⁸. These are different products with different risks, and the page on age limits for mortgages covers them in detail.

The Mortgage Charter: extending without an affordability check

The Mortgage Charter, agreed between the government and lenders in 2023, changed what a borrower up to date with payments can ask for. Lenders signed up to the Charter committed to permit customers who are up to date with their payments to extend their mortgage term, with the option to revert to their original term within six months, without assessing affordability¹⁹. The Charter covers the large majority of the market: its support for switching to a new deal at the end of a fixed rate applies to 97% of the mortgage market⁵.

The key feature is what the extension does not require. Under the Charter, if your lender has signed, you do not need an affordability check for temporary options such as extending the term or switching to interest-only for six months¹⁰. The Financial Ombudsman Service describes the measure in the same terms: extend the mortgage term to reduce monthly payments, with the option to revert to the original term within six months²⁰. The ombudsman handles complaints from borrowers who feel a Charter lender has not delivered the options it signed up to.

The Financial Conduct Authority gave this a formal footing in its 2024 rules, which created two limited exemptions from its affordability requirements, allowing lenders to vary a mortgage contract to temporarily reduce capital payments for up to six months, and to reverse a term extension within six months of it taking effect, without assessing affordability¹⁸. The exemption applies once per contract, and not to second charge or bridging loan contracts¹⁸.

There are two boundaries to know. First, the no-check extension is only for borrowers up to date with their payments. Second, affordability will need to be checked if you wish to permanently convert to an interest-only mortgage, or where the term is proposed to be extended beyond your expected retirement date⁵. The ombudsman's summary of the Charter puts the same condition on it: the term can be extended without an affordability assessment provided it does not go past your retirement age⁶.

Switching back to your original term within six months

A Charter term extension is designed to be reversible. Lenders committed to extend the term to reduce monthly payments and give customers the option to revert to their original term within six months by contacting their lender¹⁶. Citizens Advice describes the same arrangement: extending the mortgage term reduces the payments, and the option to switch back to the original term is available within six months²¹. National Debtline likewise states that lenders should also give the option to revert back to the original term within six months²².

The six-month window matters because of what happens after it. The House of Commons Library's summary of the Charter notes that customers changing mortgage terms have the option to revert to their original deal within six months without affecting their credit score²⁴. Reverting is done by contacting the lender, and under the Charter it does not need a new affordability check either¹⁹. After six months, the arrangement is no longer the temporary relief the Charter designed, and continuing on the extended term may involve an affordability assessment and could affect the credit file²⁴.

The window is also a thinking period. A borrower who extends because a fixed rate is ending, or because costs have risen sharply, has six months to see whether the lower payments have solved the problem. If they have, staying on the longer term is possible, at the price of more total interest. If the pressure was temporary, reverting restores the original end date and stops the extra interest building up.

Will it affect your credit file?

A Charter term extension, taken while you are up to date with payments, is designed not to touch your credit record: the Charter options can be taken without a new affordability check or affecting your credit score⁵. The same applies to reverting to the original term within the six-month window²⁴. So the act of extending itself is not what damages a credit file.

What does damage it is missing payments. A missed mortgage repayment can affect your credit score and stay on your credit report for up to six years²⁵. That is why the Charter's protections are tied to being up to date: once payments have been missed, the situation is an arrears case rather than a Charter case, and the record of those missed payments is what other lenders will see.

Borrowers who extend while in financial difficulty but before missing a payment get the best of both: lower payments and a clean file. Borrowers who wait until after missed payments still have options, covered next, but the arrears themselves will already be recorded. The pages on mortgage arrears and your credit file and payment holidays and credit ratings cover the detail.

Extending the term if you are already in arrears

If payments have already been missed, a term extension is still on the table, but it works differently. Advice NI lists extending the mortgage term among the standard ways of tackling mortgage arrears, alongside adding your arrears to the mortgage balance and increasing your repayments to clear the arrears²⁶. For a repayment mortgage, extending the term reduces the monthly cost of the whole loan, which can make a reduced payment affordable enough to stop the arrears growing.

The lender's decision will weigh the factors set out earlier: how large the arrears are, your age and expected retirement date, your job, and the remaining term¹⁴. Lenders in arrears situations have some flexibility about the extra payments needed to clear the arrears: if you cannot meet them, you may be able to delay those extra payments for a while or add them to your loan¹². Northern Ireland's official guidance sets out the same range of arrangements, which lenders offer depending on your payment history and whether your difficulties look short or long term¹².

Two things are different from a Charter extension. First, an arrears extension is not the once-per-contract, no-check route: it is part of a negotiated arrears arrangement, and the lender will look at your finances to set a payment you can sustain. Second, the missed payments already on your credit file remain there for up to six years²⁵, whatever arrangement follows. The priority in arrears is keeping the roof on: a mortgage is secured debt, and if the property is your home the lender will normally need a court order to repossess it²⁷. Free help is available from StepChange⁸, National Debtline²², Shelter¹⁰ and Citizens Advice²¹, and the page on what to do if you cannot pay sets out the steps.

Where a term extension may not be available

Not every mortgage can be extended. The Mortgage Charter commitments do not apply to buy-to-let mortgages²⁸, so a landlord struggling with payments on a buy-to-let mortgage cannot use the Charter's no-check extension or the six-month revert. Buy-to-let lending is treated as commercial, and arrangements are a matter for negotiation with the lender.

Bridging loans have their own rules, and they run the other way. When considering extending the term of a bridging loan, a mortgage lender must treat it as if it were a new loan, and must not agree to extend the term unless the customer has made a positive choice to do so²⁹. Bridging finance is short-term by design, and the page on regulated bridging loans covers how it works.

Other limits are practical rather than categorical. A lender will not extend past its maximum age cap⁴, and many will not extend a mortgage beyond 25 to 30 years¹⁴. Equity release products sit outside this framework altogether: a lifetime mortgage is restricted to older customers above a specified age³⁰, generally at least 55¹⁸, and is repaid from the property rather than by monthly instalments, so extending a term is not the concept that applies. Lifetime mortgages are covered on the equity release page.

Interest-only mortgages and the end of the term

An interest-only mortgage changes the question. With an interest-only mortgage you only pay the interest each month, meaning you have to pay off the entire loan at the end of the mortgage term⁷. Extending the term therefore moves the date the capital falls due, which can be a lifeline if the repayment strategy, a sale, an inheritance, savings, is not ready in time.

Lenders cannot treat this casually. Under the FCA's rules, a mortgage lender may only enter into an interest-only mortgage, or switch a repayment mortgage onto an interest-only basis for all or part of its term, if it has evidence that the customer will have in place a clearly understood and credible repayment strategy with the potential to repay the capital borrowed and any interest reasonably expected to be accrued²⁹. The same logic applies to extending the term: the lender needs to believe the capital will actually be repaid at the new end date.

If the term is ending and the capital cannot be repaid, lenders have a range of responses. They may agree to give more time to repay, especially if you could get a lump sum from things like compensation, an inheritance, selling your home, or savings and investments³¹. If the term has already ended, the options narrow further and repossession risk rises, so early contact with the lender matters. The page on what to do if you cannot pay off an interest-only mortgage covers this in full.

Help to Buy equity loans and the mortgage term

A Help to Buy equity loan runs alongside the repayment mortgage, and its term is linked to it. The equity loan term ends normally after 25 years unless extended³². The equity loan was interest-free for five years, with fees starting after that, so the timing of any change matters to the cost of the equity loan as well as the mortgage.

There is a direct interaction when the mortgage term changes. If you are increasing the length of your repayment mortgage at the same time as changing the names on the equity loan, the equity loan term may be changed to match the term of the repayment mortgage³³. Extending the mortgage term alone does not automatically extend the equity loan, so the two end dates can drift apart, and the equity loan must still be repaid, by paying it off, staircasing, or when the home is sold.

Any remortgage while the equity loan is outstanding needs the administrator's permission, and the rules allow some flexibility in hard cases: the scheme may allow you to borrow more on your repayment mortgage to pay off leasehold arrears or mortgage arrears, considered individually³⁴. Borrowers should also remember the scheme's own conditions, including not buying a second property while you have a Help to Buy: Equity Loan, which is a breach of the terms and requires you to repay the equity loan in full³². The page on remortgaging with a Help to Buy equity loan covers the process.

Advice, fees and where to get free help

Whether to extend a term is a decision with two costs attached: the extra interest over the longer life of the loan, and any fee the lender charges for the change. Lenders decide individually whether a fee applies, so ask directly before agreeing. The Building Societies Association's guidance is to contact the lender directly, or speak to an independent mortgage adviser, to see what is most suitable for your needs³. The page on mortgage advice explains the difference between advice from a lender, a broker and an adviser.

Free, impartial help exists at every stage. If payments are hard but manageable, MoneyHelper offers free guidance, and the Mortgage Charter's own options are there to be used⁵. If payments are not manageable, debt charities including StepChange⁸ and National Debtline²² give free advice on mortgage arrears, and Shelter¹⁰, Citizens Advice²¹, Shelter Cymru¹⁴, Housing Rights in Northern Ireland¹ and Advice NI²⁶ advise on keeping the home. Scope advises disabled people and their families on mortgage problems²⁵.

If a Charter lender does not deliver the options it signed up to, or an arrears arrangement is handled badly, the Financial Ombudsman Service can investigate complaints about financial difficulties with mortgages⁶, and its data shows the Charter options being used by borrowers in difficulty²⁰. Complaints go to the lender first, then to the ombudsman, free of charge.