How much can you actually borrow? This calculator shows both limits lenders apply — the headline income multiple (about 4.5× salary) and a net take-home budget cap driven by real 2026/27 take-home pay — then binds on the lower and stress-tests it, so you get a realistic maximum property price, not an optimistic one.
7 min read·Updated Fri Aug 21 2026 00:00:00 GMT+0000 (Coordinated Universal Time)·🇬🇧 UK
Calculator
Income
£
Joint application (add a second income)
£
£
The mortgage
£
%
%
Apply FCA-style stress test i
Tax details (for take-home)
Scottish taxpayer
What you could borrow
Property price = deposit + loan
Your result
Enter your income and deposit, then press Calculate.
Embed this calculator
Add this free calculator to your own site — it stays up to date automatically. Copy the snippet below; it drops in a responsive widget plus a credit link back to the source. Free to use with the attribution link kept in place.
By embedding you agree to keep the visible attribution link intact. The widget loads only the calculator — no ads or site navigation.
Key takeaways
Key takeaways · 2026/27
Lenders apply two tests and you get the lower of them: an income multiple (typically 4.5× gross income) and an affordability check on your net take-home pay.
A £50,000 salary at 4.5× borrows up to £225,000 — but existing debts, student loans or a stress test can pull the binding figure below that.
Max property price = maximum loan + your deposit. A bigger deposit raises your price ceiling and lowers your LTV, which unlocks better rates.
A joint application adds a second income to the multiple, usually the single biggest lever on how much you can borrow.
Lenders must stress-test affordability at a higher future rate — so the amount you can borrow today assumes rates could rise.
How it works
How much can I borrow — the two tests lenders actually run
Ask "how much can I borrow?" and most calculators just multiply your salary by 4.5. Real lenders run two checks and give you the lower of them. The first is the income multiple: about 4.5 times your gross income, capped by regulation. The second is an affordability assessment built from your net take-home pay — what actually reaches your bank after tax, National Insurance, pension and student loan — because that is what has to cover the mortgage alongside your other bills.
This page does both. The income-multiple cap comes straight off your gross salary. The budget cap starts from real 2026/27 take-home (the same engine as our take-home pay calculator), takes a sensible share of it for housing (35% by default), subtracts your existing debt payments, and then works backwards from that affordable monthly payment to the largest loan it can service at your rate and term. Whichever cap is lower is the one that binds — and the calculator tells you which, so you know which lever to pull.
Worked example: £50,000 salary, £30,000 deposit
Take a single applicant on £50,000 with a £30,000 deposit, at 4.5% over 30 years:
Income-multiple cap: £50,000 × 4.5 = £225,000.
Maximum property price: £225,000 loan + £30,000 deposit = £255,000, an LTV of about 88%.
Monthly repayment on £225,000 at 4.5% over 30 years is roughly £1,140 a month, which comfortably fits inside the take-home budget — so here the income multiple is the binding limit.
Now add £600 a month of existing debt payments (a car-finance and a loan, say). That drops the affordable housing budget sharply, and the net-income budget cap falls below the £225,000 multiple cap — so the binding figure, and the label on the result, switches to the take-home budget. Clearing that debt would hand the borrowing back. Turn on the stress test and the budget cap is recomputed at a higher rate (here 6%), trimming it again — which is exactly what a lender does before making you an offer.
The deposit does double duty. It adds pound-for-pound to your maximum property price and lowers your loan-to-value. Dropping from 90% to 85% or 75% LTV typically unlocks a lower interest rate, so a slightly bigger deposit can both raise your ceiling and cut the monthly cost.
The levers that change what you can borrow
Four inputs move the answer most: a joint application adds a second income to the multiple cap (usually the biggest single lever); clearing existing debt frees up the take-home budget cap; a larger deposit raises the price ceiling and improves your rate; and a longer term lowers the monthly payment, which lifts the budget cap (at the cost of more total interest — check that on the mortgage repayment calculator).
A planning tool, not a mortgage offer or financial advice. Lenders use their own income multiples, expenditure models and stress rates, and assess credit history, job stability, bonuses and benefits that this tool does not. Income-multiple, net-housing-share and stress-test assumptions are documented and dated in the site's audited assumptions file. Verify your position with a qualified mortgage adviser and get a Decision in Principle before relying on any figure.
Frequently Asked Questions
How much can I borrow for a mortgage?
Most UK lenders will lend up to about 4.5 times your gross annual income, though a minority stretch to 5–5.5× for higher earners or certain professions. On a £50,000 salary that is roughly £225,000. But the income multiple is only the first test: lenders also run an affordability assessment on your monthly take-home pay, and you are offered the lower of the two. Existing debts, student loan repayments and childcare costs all reduce the affordability figure, so your real maximum can be well below the headline multiple.
Do mortgage lenders use gross or net income?
Both, for different tests. The headline income multiple (around 4.5×) is applied to your gross salary. The separate affordability check works from your net take-home pay — what actually lands in your account after tax, National Insurance, pension and student loan — because that is what pays the mortgage and your living costs. This calculator does both: it applies the multiple to gross income and drives the budget cap from real 2026/27 take-home, then binds on whichever is lower.
What income multiple do mortgage lenders use?
The mainstream cap is about 4.5 times income, and the financial regulator limits how much of a lender's book can go above that. Some lenders offer 5× or even 5.5× to high earners, professionals (doctors, lawyers, accountants) or through specialist schemes. You can adjust the multiple in this calculator between 3.0× and 5.5× to see the effect, but treat anything above 4.5× as lender-specific rather than the norm.
How much deposit do I need?
Your maximum property price is your maximum loan plus your deposit, so the deposit directly raises your ceiling. It also sets your loan-to-value (LTV): a £30,000 deposit on a £255,000 property is about 88% LTV. Lenders reserve their best rates for lower LTVs — the meaningful thresholds are usually 90%, 85%, 75% and 60% — so a slightly larger deposit that drops you into a lower LTV band can cut your interest rate as well as increase what you can buy.
What is a mortgage stress test?
Since the affordability rules, lenders must check you could still afford your mortgage if interest rates rose, rather than only at today's rate. This calculator models that by testing your take-home budget cap at the higher of your entered rate plus one percentage point or a 6% floor. With the stress test on, the budget cap — and therefore your binding maximum loan — is lower, which is closer to what a lender will actually offer.
Is a mortgage affordability calculator accurate?
It gives a realistic guide, but every lender scores affordability slightly differently — they use their own income multiples, expenditure assumptions, stress rates and treatment of debts, bonuses and benefits. Use this as a planning tool to understand the levers (deposit, debts, joint income, term), then get a Decision in Principle from a lender or broker for a figure you can rely on. It is not a mortgage offer or financial advice.
Disclaimer: Figures are estimates based on 2026/27 rates and rules and may change. Verify with HMRC or a qualified adviser before making financial decisions.