Find out how much you could borrow — with income multipliers, debt-to-income ratio and stress test.
What this calculator estimates. An indicative maximum borrowing figure from the income multiple you select, converted into a property value using your deposit, and into a monthly payment using your rate and term. On a £50,000 salary a 4.5× multiple starts at £225,000 and a 4× multiple at £200,000 — the multiple you choose, not the tool, drives most of that difference.
What moves the number. Gross income (single or joint), the multiple applied, existing monthly commitments, the deposit and the term. Commitments reduce capacity because a lender assesses what is left once they are paid.
What it assumes. Basic salary as entered, a capital repayment mortgage, one constant interest rate for the whole term, and the multiple you select. It applies no lender’s own credit scoring.
Why this is an estimate and not a lender offer. Each lender sets its own income rules, credit policy and stress margin and assesses your full circumstances, so a real offer is often lower than an income-multiple estimate.
An affordability estimate is not the lender stress test. This page answers how much might I borrow? Separately, a lender must check that you could still afford the repayments if rates rose — a different test, with its own margin. That is explained in the UK mortgage stress test.
How sensitive is your number? UKCalc quantifies what a rate move, a bigger deposit or a longer term actually changes in the mortgage rate sensitivity analysis.
| Combined annual income | — |
| Income multiplier | — |
| Maximum borrowing | — |
| Deposit | — |
| Estimated property value | — |
| Loan-to-value (LTV) | — |
| Monthly commitments (existing) | — |
| Monthly mortgage payment | — |
| Total monthly outgoings | — |
| Total interest payable | — |
| Total repaid over term | — |
| Year | Balance | Principal paid | Interest paid | Cumulative interest |
|---|
UK mortgage lenders use income multiples as a starting-point filter. The most common multiples are:
| Multiplier | Typical applicant | Example (£50k salary) |
|---|---|---|
| 4× income | Conservative — older borrowers, high commitments | £200,000 |
| 4.5× income | Standard — most high-street lenders | £225,000 |
| 5× income | Higher earners or specialist lenders | £250,000 |
| 5.5×+ income | Professional mortgages (doctors, lawyers, etc.) | £275,000+ |
Income multiples apply to basic salary. Many lenders will also consider regular overtime, bonuses (usually 50–100% of the amount) and self-employed profits based on 2–3 years of accounts. Rental income from buy-to-let properties is assessed differently.
UK lenders must check that borrowers could still afford repayments if mortgage rates rose above the initial deal rate. The requirement itself comes from the FCA's affordability rules (MCOB 11), which oblige lenders to consider likely rate rises over at least the first five years of the loan.
The separate Bank of England recommendation to test at 3 percentage points above the reversion rate was withdrawn in August 2022. Lenders still stress-test, but they now set their own margins — commonly 1–3% above the pay or reversion rate, often subject to an internal floor. That is one reason a lender's actual offer is often lower than a simple income-multiple calculation suggests. Our mortgage stress test calculator models the effect at your own figures.
Your debt-to-income ratio is the percentage of your gross monthly income consumed by all debt payments — including the new mortgage. Most UK lenders have informal DTI limits:
Existing debts — car finance, personal loans and credit card minimum payments — count toward this ratio and directly reduce the mortgage you qualify for. Clearing a car finance agreement before applying, for example, can meaningfully increase your borrowing capacity.
| LTV | Deposit needed | Rate tier | Notes |
|---|---|---|---|
| 95% LTV | 5% | Highest rates, limited choice | Government-backed schemes available |
| 90% LTV | 10% | Significantly better | Mainstream lenders re-enter at this tier |
| 85% LTV | 15% | Good rates | Most lenders' full product range |
| 75% LTV | 25% | Very competitive | Best-buy tables typically start here |
| 60% LTV | 40% | Lowest rates available | Remortgagers with significant equity |
For joint mortgages, lenders typically use the combined income of both applicants to determine the income multiple. Some lenders apply the multiple to the first applicant's income and add a smaller multiple (or the full salary) of the second — but the more common approach is simply to multiply the combined total. Both applicants' credit histories are assessed, and the weaker credit file can affect the rate or outcome. Both applicants are jointly and severally liable for the full mortgage debt.
Your credit score does not directly determine how much you can borrow, but it significantly affects the interest rate you are offered. A poor credit history — missed payments, defaults, CCJs, or a high credit utilisation ratio — can result in being rejected by mainstream lenders or being offered a higher rate. Before applying, it is worth checking your credit file with all three main agencies (Experian, Equifax and TransUnion) and correcting any errors. Most lenders run a hard credit search when you formally apply, which leaves a mark on your file. If you have a student loan, missed payments or defaults, our guide to getting a mortgage with a student loan or bad credit walks through what lenders actually check.
Following the Bank of England's base rate cycle, UK fixed mortgage rates in 2026 typically range from around 4–5% for 2-year and 5-year fixes, depending on LTV and lender. Tracker rates are directly tied to the base rate. The choice between a 2-year and 5-year fix involves weighing the certainty of a longer fix against the flexibility of a shorter one — if rates fall significantly, a 2-year fix allows earlier remortgaging. Arrangement fees (typically £999–£1,999) should always be factored into the total cost comparison between deals.
Three UK mortgage scenarios showing how income, deposit, commitments and multiplier interact — using 2026 market rate estimates.
The Patels' high DTI (47%) illustrates how childcare costs reduce affordability. Their lender applied a 4× multiplier rather than 4.5× due to their commitments — reducing borrowing by £37,000 compared to 4.5×. Reducing or ending the loan before applying would cut their DTI to ~44%. Not financial advice.
Lender rules, regulatory requirements and UKCalc assumptions — kept separate. Checked on 2 September 2026.
Official figures this calculator applies
UKCalc assumptions — not official figures
This is an estimate, not a decision in principle. Two lenders assessing the same applicant routinely differ by tens of thousands of pounds, because affordability models, stress rates and treatment of variable pay all differ.