Mortgage affordability calculator
See a realistic borrowing estimate based on your income and deposit. Worth having your own number before a lender gives you theirs, and worth knowing what would move it.
Updated for the 2026/27 tax year · reviewed
Your income and deposit
= 10.0% of budget
Typical lender multiple - most UK lenders offer 4-4.5×, some stretch to around 5.5× for higher earners. Real lenders run their own affordability tests on top of this multiple, weighing your debts, credit history and outgoings.
Indicative property budget
£400,000
£80,000 income × 4.5 + £40,000 deposit
Borrowing amount
£360,000
Deposit as % of budget
10.0%
Indicative loan-to-value
90.0%
Indicative monthly payment
£1,824
at 4.5% stress rate
Share of gross income on mortgage
27.4%
indicative monthly payment ÷ monthly gross income
Deposit + stamp duty up front
£50,000
deposit plus the stamp duty figure below
Stamp duty (SDLT)
Auto-calculated from the indicative budget above using England rates - Scotland and Wales use different rates and bands.
Estimated stamp duty
£10,000
on a £400,000 purchase
Know the real figure for your purchase? Override it here - the rest of the page keeps using the auto figure until you do.
Budget by income multiple
How your indicative budget changes at a lower or higher lender multiple.
A lender's ceiling isn't the same as your comfort.
Borrowing the maximum is survivable on paper and tight in real life. See what each borrowing level does to your monthly surplus, your savings rate and your pension contributions before you commit.
Create your free accountHow this calculator works
We multiply your income (or combined income, for a joint application) by a lender income multiple - 4.5× by default, adjustable between 3.5× and 5.5× - to estimate the borrowing amount, then add your deposit on top to get an indicative property budget. The indicative monthly payment tile applies that borrowing amount to the standard UK repayment formula at 4.5% over 30 years, just to give a rough sense of scale.
Real UK lenders don't stop at a simple income multiple. They run their own affordability stress tests - checking you could still afford payments at a higher notional rate - and weigh existing debts, credit history, dependants and monthly outgoings, none of which this simplified calculator models. The multiple you actually get can be higher or lower than the one shown here.
Treat the budget above as a starting point for house-hunting, not a mortgage offer. The bar chart shows how sensitive that budget is to the multiple - worth checking before you get attached to a number at the top of the range.
Questions people ask
How much can I borrow based on my income?
Most UK lenders offer between 4 and 4.5 times your annual income, though some stretch to around 5.5× for higher earners or specific schemes. This calculator uses a configurable multiple, defaulting to 4.5×, so you can see how the range shifts your borrowing power.
What counts as income for a mortgage application?
Basic salary is always counted; regular bonuses, commission and overtime are often included at a reduced percentage, and rental or self-employed income needs one to three years of accounts or tax returns. Lenders vary, so treat this as a starting estimate rather than an offer.
How does my deposit affect what I can borrow?
A bigger deposit lowers your loan-to-value (LTV), which usually unlocks cheaper rates and, for some lenders, slightly higher income multiples. Below a 10% deposit, product choice narrows and rates tend to be noticeably higher.
Why might a lender offer me less than this estimate?
Real affordability assessments run a stress test on your ability to pay at a higher notional rate, and weigh existing debts, credit history, dependants and outgoings - none of which this simplified calculator models. Use it to gauge the ballpark, then get a decision in principle from a lender or broker.
Last reviewed against 2026/27 UK rules. Projections are estimates for education, not financial advice. Understanding your projections.
A calculator answers one question at a time.
The planner keeps all of them next to each other, so an overpayment you model today still shows up in the pension picture in twenty years.
- Free to start
- No card needed
- Your figures carry over