Fixed vs variable rate mortgage UK: which should you choose?

If you're weighing up a fixed vs variable rate mortgage UK lenders offer, it helps to start with what each option actually means for your monthly budget.

A fixed rate mortgage locks your interest rate for an agreed period, typically 2, 3, 5, or 10 years. Whatever happens to the Bank of England base rate during that time, your monthly payment stays exactly the same.

Once your fixed term ends, your mortgage automatically moves to your lender's standard variable rate (SVR) unless you arrange a new deal beforehand, whether that's a new fix, a tracker, or a remortgage with a different lender.

One thing to check carefully: most fixed rate deals carry an early repayment charge (ERC) if you leave the deal before the term ends, for example by overpaying beyond your allowance, remortgaging early, or selling the property without porting the mortgage. Porting a mortgage when you move home can help you avoid this charge.

A variable rate mortgage has an interest rate that can move up or down during your deal, rather than staying fixed. Your monthly payment changes in line with the rate.

There are three main types available in the UK:

• Tracker mortgages, which follow the Bank of England base rate plus a set margin
• Standard variable rate (SVR) mortgages, which follow your lender's own default rate
• Discount rate mortgages, which offer a discount off the lender's SVR for a set period

We'll cover each of these in more detail below, as the differences matter when you're deciding which suits your situation.

Once you understand how each mortgage type works, it helps to see the fixed vs variable rate mortgage differences side by side.

None of these options is automatically the "right" choice. Each row in this table represents a trade-off between certainty and flexibility, and the best fit depends on your budget, your plans, and how much risk you're comfortable carrying.

The type of mortgage you choose affects how exposed you are to interest rate changes, and that has a real impact on what you can afford.

With a fixed rate, your payment is protected for the whole term, so a base rate rise during that period doesn't affect your budget at all. The trade-off is that if rates fall, you won't benefit until your fixed term ends.

With a tracker or SVR mortgage, your payment moves with the market. If the Bank of England raises rates, your payment rises too, sometimes within weeks. It's worth working out, before you commit to a variable rate, whether your budget could absorb a meaningful rate increase without falling into arrears.

Your home may be repossessed if you do not keep up repayments on your mortgage or any other debt secured on it. This is exactly why lenders and advisors stress-test affordability before approving a variable rate deal, and why it's worth doing the same exercise for yourself before you choose.

If budgeting for a rate rise feels uncertain, or you're worried about affordability more generally, MoneyHelper (moneyhelper.org.uk, 0800 138 7777) offers independent, government-backed money guidance.

Moving home creates a specific decision point that doesn't apply if you're staying put: you have to choose a mortgage product for the new property, and the deal you already have may or may not come with you.

Can you port your existing deal? Many fixed and some variable deals are portable, meaning you can transfer your current rate to the new property rather than starting fresh. This can help you avoid an early repayment charge, but you'll still need to pass fresh affordability checks, and if the new mortgage is larger, the extra amount is usually arranged at a current rate. Our porting a mortgage guide covers how this works in more detail.

How long do you plan to stay? If you expect to move again within a couple of years, a shorter fix or a tracker with low or no early repayment charges may suit better than tying yourself into a long deal. If this is a long-term family home, a longer fix can offer years of payment certainty.

What's the rate outlook? If the market expects the Bank of England to cut rates further, a tracker could capture the benefit automatically. If cuts are expected to stall or reverse, locking in a fix sooner rather than later may be the more cautious approach. These are always forecasts, not guarantees, so it's worth discussing the latest outlook with an advisor rather than relying on assumptions.

Before you commit, it's worth getting a clear picture of how much you can borrow and using a mortgage in principle to strengthen your position when you make an offer. Our mortgage application timeline guide sets out what to expect at each stage once you've decided.

This guide is part of our broader moving home mortgages series, which covers every stage from application to completion.

High-street banks can only offer their own fixed and variable products, and comparison websites typically show a limited slice of the market. A mortgage advisor who compares a wide range of lenders can look at deals from banks, building societies, and specialist lenders in one place, including some that aren't available directly to the public.

An advisor can model how a fixed and a variable option would each play out against your actual loan-to-value, income, and credit profile, rather than a generic example. They can also check whether porting is worth it in your situation, work through the maths on any early repayment charge, and advise on timing if you're weighing up moving before or after a rate decision.

All mortgage advice given by Financial Conduct Authority-regulated firms must meet standards designed to protect you, including assessing whether a recommendation is suitable for your circumstances. You can check any firm's authorisation on the Financial Conduct Authority Register.

Your home may be repossessed if you do not keep up repayments on your mortgage or any other debt secured on it.