Remortgage Guide UK 2026: When to Switch, Fees to Check, and Worked Example

Remortgaging is one of those jobs homeowners often leave until the letter from the lender arrives. That can be expensive. When a fixed or discounted mortgage deal ends, many borrowers move onto a standard variable rate, which may be higher than a new deal. This guide explains how remortgaging works, when to start, how to compare rates and fees, and how to avoid focusing only on the headline rate.

What remortgaging means

Remortgaging means replacing your current mortgage deal with a new one, either with the same lender or a different lender. If you stay with the same lender, it is often called a product transfer. If you move lender, the new mortgage pays off the old one.

People remortgage to avoid a higher standard variable rate, reduce monthly payments, fix a rate for certainty, borrow more, change the mortgage term or move to a different type of deal. MoneyHelper notes that remortgaging can cut costs, but also warns that borrowing more over a longer term can increase the total amount repaid.

For a quick estimate, use our remortgage comparison calculator. It compares your current rate with a new deal, including product fees, exit costs, monthly saving and break-even point.

When to start comparing

A common approach is to start looking around six months before your deal ends. Some mortgage offers are valid for several months, which can let you secure a rate early and still switch when your current deal finishes. This can be useful if you are worried about moving onto a higher standard variable rate.

Check your current mortgage documents before making decisions. The key items are your current balance, remaining term, current interest rate, deal end date, early repayment charge and exit fee. You can then compare the current deal with new options using the mortgage calculator and remortgage comparison calculator.

Fees, rates and true cost

The lowest interest rate is not automatically the cheapest mortgage. A deal with a £999 or £1,499 product fee may be cheaper for a large mortgage but poor value for a smaller mortgage. Some deals also include valuation fees, legal fees or cashback. If you leave your current deal early, an early repayment charge can wipe out the saving.

Compare deals over the period you expect to keep them. For a 2-year fix, look at the cost over 2 years. For a 5-year fix, compare over 5 years. If you add a product fee to the mortgage, remember that the fee becomes part of the balance and can accrue interest.

Worked example

Suppose you owe £220,000 with 25 years left. Your current standard variable rate is 6.5%. A new 2-year deal offers 4.8% with a £999 product fee and no exit fee. On a repayment basis, the current payment is about £1,486 a month. The new payment, with the fee added to the balance, is about £1,267 a month. That saves about £219 a month.

Over 24 months, the gross monthly saving is about £5,256. The break-even point is roughly 4.6 months because the £999 fee is recovered through the monthly saving. In this example, the new deal looks cheaper over the 2-year comparison period. Change the balance, rate, fee or term and the answer can change quickly.

What to check before switching

Check affordability as well as rate. A lender can reassess income, outgoings, credit file, property value and loan-to-value. If your property value has increased or your balance has fallen, you may have moved into a lower loan-to-value band, which can improve rates. If income has fallen or debts have risen, borrowing options may be more limited.

Our mortgage affordability calculator helps estimate borrowing range, while the debt-to-income calculator shows how monthly payments compare with income. If you are deciding whether to reduce the balance before switching, try the mortgage overpayment calculator.

For broader context, read our mortgage affordability guide and mortgage deposit guide. They cover income multiples, loan-to-value and the costs around buying or refinancing a home.