Last reviewed: June 2026
TL;DR- Extending the mortgage term reduces monthly payments by spreading the remaining balance over a longer period.
- A longer term means more months of interest, significantly increasing the total amount repaid over the life of the mortgage.
- Lenders apply age-at-end-of-term limits (typically 70-80) which restrict how far the term can be extended for older borrowers.
- Term extension can be arranged as a forbearance measure, at remortgage or as a product transfer with most lenders.
Why Borrowers Extend Their Mortgage Term
The main driver for mortgage term extension is to reduce monthly payments. A longer term spreads the outstanding balance over more months, reducing each monthly payment. This can be valuable for: borrowers facing affordability pressure due to rate increases; those whose income has reduced temporarily; first-time buyers or movers who want to maximise their purchasing power by reducing the monthly cost; and borrowers approaching their deal end date who want to remortgage but find the shorter remaining term makes payments too high.
The FCA has noted that average mortgage terms have lengthened in the UK as a result of affordability pressures. Terms of 30 and 35 years are now common; some lenders extend to 40 years. The Bank of England and FCA have highlighted concerns about borrowers entering or remaining in mortgage debt into retirement.
The Total Cost Trade-off
Extending the term significantly increases the total interest paid. On a £200,000 mortgage at 5%, extending from a 20-year to a 30-year term reduces the monthly payment from approximately £1,320 to £1,074 - a saving of £246 per month. However, the total interest paid increases from approximately £116,000 to approximately £187,000 - an additional £71,000 in interest over the extended term. This trade-off must be understood before agreeing to a term extension.
How to Extend the Term
A term extension can typically be arranged in three ways: by requesting a term extension from the existing lender (which may require an affordability assessment if payments are maintained or a simpler process if this is a forbearance measure); at the point of remortgage to a new lender (the new term is agreed as part of the new mortgage); or as part of a product transfer. The lender must confirm that the borrower will be within the maximum age at end of term and that affordability is maintained at the new payment level.
Age and Term Limits
Lenders impose maximum ages at end of mortgage term - typically 70-80 years. Extending the term may not be possible for older borrowers if the new end date would exceed the lender's maximum age. A 65-year-old borrower with a mortgage ending at 70 may not be able to extend to 80 unless the lender's maximum age permits it. Where age limits restrict term extension, later-life mortgage products (RIO, lifetime mortgage) may be alternatives.
Frequently Asked Questions
Can I extend the term of my mortgage mid-deal without remortgaging?
Some lenders allow a term extension as part of their product transfer or existing mortgage management process, without requiring a full remortgage. Others require the borrower to wait until the deal period ends and then extend at the point of product transfer or remortgage. The specific process varies by lender and should be confirmed directly with the mortgage lender.
If I extend my term now, can I shorten it again later?
Yes. Term extension is not permanent. Borrowers can subsequently shorten the term by: overpaying the mortgage to build up capital more quickly; requesting a term reduction from the lender (which increases monthly payments); or remortgaging to a shorter term when the deal ends. The flexibility to manage the term over time is one of the reasons that term extension as a temporary measure can be appropriate without locking in the longer term permanently.
Does extending the term affect the interest rate on my mortgage?
A term extension on its own does not typically change the interest rate on the current deal. The rate and deal terms remain the same; only the payment amount and total term change. At the next product switch or remortgage, the new rate is selected independently of the term decision - the term and the rate are separate choices.
Is a term extension the same as rolling up interest?
No. A term extension maintains regular payments but spreads them over more months, reducing the monthly amount. Rolling up interest (as in a lifetime mortgage or during a payment holiday) means no payments are made and interest is added to the outstanding balance. A term extension still requires monthly payments - they are simply lower for longer. Rolling up interest results in a growing outstanding balance; a term extension does not.
