Enter your gross monthly income, existing debts, and deposit. The 28/36 rule gives you a conservative maximum purchase price — and this page covers stamp duty, Help to Buy, and LISA context specific to buying in the UK.
A UK buyer earning £5,000/month gross with £200/month in existing debts and a £58,000 deposit: the housing cap is £1,400 (28%) and the total-debt cap leaves £1,600 for housing. Binding limit is £1,400/month.
At 4.8% over 25 years, £1,400/month services a loan of approximately £240,000. Adding the £58,000 deposit gives a maximum affordable price of roughly £298,000. A £290,000 target fits; anything above £298,000 would exceed the guideline.
UK note: A £290,000 purchase in England attracts stamp duty of approximately £2,000 (£0 on first £125k; 2% on next £125k; 5% on remaining £40k = £2,500 total for standard buyers; first-time buyers pay 0% up to £300,000 so likely £0 here). Factor this into your deposit planning.
The 28/36 rule is a widely-used affordability benchmark. UK mortgage lenders typically run their own affordability stress tests (often at a rate 3% above the product rate), but the 28/36 rule gives a conservative planning number that aligns closely with what high-street lenders approve in practice.
In a UK context: UK lenders typically lend 4–4.5× income. If the 28/36 calculation returns a higher figure than 4.5× your annual income, use the lower income-multiple as your practical cap. Most first-time buyers in England should also budget for stamp duty and solicitor fees of roughly 1–2% of the purchase price on top of the deposit.
The 28/36 rule is a lending guideline: housing costs should not exceed 28% of gross monthly income, and total debts should not exceed 36%. UK lenders often apply their own stress-test models but the 28/36 rule provides a useful conservative estimate.
It takes the tighter of the two rule limits as the maximum monthly payment, solves the amortisation formula in reverse to find the maximum loan, and adds the deposit to get the maximum purchase price.
From April 2025, SDLT in England: 0% on the first £125,000; 2% on £125,001–£250,000; 5% on £250,001–£925,000; 10% on £925,001–£1.5m; 12% above £1.5m. First-time buyers pay 0% up to £300,000 and 5% on £300,001–£500,000. Verify with HMRC for current rates.
Yes. Save up to £4,000/year into a LISA and receive a 25% government bonus (up to £1,000/year). Funds can be used toward a first home worth up to £450,000. Withdrawing for any other purpose before age 60 incurs a 25% penalty that claws back more than the bonus.
The Help to Buy equity loan scheme closed to new applications in March 2023. The Mortgage Guarantee Scheme allows lenders to offer 95% LTV mortgages on properties up to £600,000. First Homes offers discounts of 30–50% on market value to key workers and local first-time buyers. Shared Ownership lets you buy a 10–75% share and pay subsidised rent on the rest.
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