Find out what you could afford to repay
This calculator uses the income and outgoings you enter to estimate what you could comfortably afford to repay each month. It's a figure based on your own numbers, not a lender's decision, and won't match every lender's own affordability check.
How to use the Affordability calculator and read your result
The Affordability calculator gives you a working figure for what you might be able to borrow, based on the income, outgoings and mortgage details you put in. This guide is for anyone who wants to understand what that figure means before using it in a conversation with a lender or broker. It walks through what to enter, what the result shows, and where its limits are.
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Enter your income and outgoings
You enter your income, your regular outgoings and your outstanding balance, the same figures a lender would ask for.
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Add your mortgage details
You add your remaining term and current rate so the calculator can work out what a new monthly repayment might look like.
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Understand what the result means
You see what the figure does and does not tell you, and what to check before treating it as a lender's answer.
Mortgage Affordability Calculator
Estimate how much you could borrow for a mortgage based on your household income, regular outgoings, and typical lender stress-test rates. This gives you an indicative borrowing range before you speak to a lender or broker.
Your Indicative Results
How this calculator works
This tool produces an indicative borrowing estimate using two industry-standard checks and taking the lower of the two:
- Income multiple: Your total assessed annual income multiplied by the income-multiple cap (typically 4.5×).
- Affordability & stress test: Your monthly disposable income (income minus outgoings, dependant costs and credit commitments) is used to work out the largest loan whose repayment — calculated at the lender's higher stress-test rate — you could still afford.
Lenders "stress" your ability to pay at a rate higher than the initial pay rate to ensure you could cope if interest rates rose. We apply a repayment (capital & interest) formula over your chosen term at that stress rate.
Important: This is a guide only and not a mortgage offer or financial advice. Actual lending decisions depend on credit history, individual lender criteria, and a full assessment of your circumstances. Always speak to a qualified mortgage adviser.
See what you could afford before you call anyone
This calculator takes your income, outgoings and mortgage details and works out a figure a lender might consider affordable. It's built for homeowners checking their position ahead of a remortgage. The result is a starting point, not an offer or a guarantee from any lender.
No sign-up, no data stored, free to use.
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