Mortgage Affordability Calculator UK 2025

Most high street lenders will offer 4–4.5 times your annual salary if you're applying alone, or 3.5–4 times joint income. So on a £50,000 salary with a £25,000 deposit, you're looking at roughly £200,000–£225,000 borrowing, which means a property up to about £250,000. Some specialist lenders go to 5.5x for high earners with spotless credit, but they're the exception.

Quite a bit. A strong credit score doesn't just get you approved — it gets you better rates, which means lower monthly payments, which means you pass the affordability checks more easily. Poor credit could knock 0.5x off your income multiplier and add 1–2% to your rate. Before you apply, check your Experian, Equifax, and TransUnion reports for errors. Even a wrong address can cause problems.

Yes, but lenders want proof your income is stable. Most ask for 2–3 years of accounts or SA302 tax calculations from HMRC. They'll also typically offer a slightly lower multiplier — around 0.5x less than employed applicants. Tip: if you're self-employed, use an accountant. Clean, consistent accounts make a huge difference to what lenders will offer you.

It's a check that you could still afford your repayments if rates jumped. The lender adds about 3% to the rate they're offering you (or uses a floor of around 7–8%) and checks whether you could still pay. You might comfortably afford £1,200/month at 5%, but at 8% that same mortgage costs £1,600. If that pushes you over the limit, you'll get a smaller offer. It's a Bank of England requirement, not something the lender can waive.

The minimum is 5% for most lenders. But the rates at 5% are pretty steep. At 10%, they improve noticeably. At 15–20%, you're into the best deals on the market. Every extra bit of deposit also means you can afford a more expensive property, so it compounds. The Lifetime ISA gives first-time buyers a 25% government bonus on savings up to £4,000/year — that's free money toward your deposit.

Yes, a lot. Lenders add up all your monthly commitments — credit cards, car finance, personal loans, student loans — and calculate your debt-to-income ratio. If you're spending more than 30% of your monthly income on debt repayments, most lenders will cut their offer significantly. One practical move: pay off small debts before applying. Even clearing a £100/month car payment can add £20,000+ to your borrowing capacity.

Yes. Each child reduces what lenders will offer because they factor in childcare and living costs. The hit is typically around 0.1x per dependent, so two kids might reduce your multiplier from 4.5x to 4.3x. On a £50,000 salary, that's a £10,000 reduction in borrowing.

Joint applications add both incomes together, so you can borrow more overall. But the multiplier drops — usually 3.5–4x combined rather than 4–4.5x solo. Both applicants are jointly and severally liable, meaning the bank can chase either person for the full amount if payments stop. Some lenders offer "joint borrower, sole proprietor" where a parent can boost your income on the application without going on the property title.

Sometimes — a few lenders offer slightly better multipliers or preferential rates for first-time buyers. The bigger benefit is stamp duty relief: you pay nothing on the first £425,000 on properties up to £625,000, which saves you thousands compared to a home mover buying the same place.

It'll get you in the right ballpark, but every lender runs their own affordability model with different assumptions about living costs, spending habits, and risk. The figure here is based on typical UK lending criteria. For a real answer, get a mortgage agreement in principle — it takes about 15 minutes online and doesn't affect your credit score with most lenders.