All calculators

UK Mortgage Affordability Calculator

Estimate an illustrative mortgage and property-price range from your income, deposit, monthly commitments and mortgage assumptions.

Your details

Your household income

Applicant 1

£

Gross annual income before tax and deductions.

£

Optional. Overtime, bonus, commission, self-employed or other variable income.

%

Choose the share you want included in this illustration. Lenders may assess variable income differently.

Your deposit and buying costs
£

£

Keep aside money for costs such as Stamp Duty/Land Tax, legal fees, surveys, mortgage fees and moving.

Existing monthly commitments

Include payments you expect to continue after buying, such as loans, car finance, credit-card minimums, child maintenance and other contractual commitments.

£

Essential monthly household costs

Enter regular household costs you expect to continue after buying, excluding the mortgage payment and owner-only property costs entered below. Use costs you consider essential or difficult to reduce.

£

Estimated owner-only monthly costs

Avoid double counting. For example, include Council Tax either in household costs or owner-only costs — not both.

£

£

£

£

Mortgage assumptions
%

Annual interest rate for this illustration.

years

Full repayment term, not just an introductory deal period.

%

A higher rate used to see how the payment could change. This is your planning assumption, not a lender stress test.

×

A planning multiple applied to usable annual income. It is not a lender offer or guarantee.

£

An amount you choose to leave after regular costs and the modeled mortgage payment.

Test a property price (optional)
£

See the mortgage, deposit percentage and payments this property would imply under your entered assumptions.

Your illustrative UK mortgage affordability range

Based on gross household income, monthly costs, deposit and mortgage assumptions you entered. This is not a mortgage offer, approval decision or affordability assessment.

Illustrative borrowing limit
£270,000
Illustrative property price
£305,000
Mortgage payment at current rate
£1,578.39
Payment at stress rate
£1,908.30

Your selected income multiple produces the lower illustrative borrowing limit under these inputs.

Lenders may use different income treatment, spending assumptions, stress tests and credit criteria.

Borrowing calculation

Usable income, income-multiple ceiling, payment budget and illustrative borrowing limit
Usable annual household income£60,000
Gross monthly income equivalent£5,000.00
Indicative income multiple4.5×
Income-multiple borrowing ceiling£270,000
Monthly payment budget after entered costs/buffer£2,250.00
Loan supported at current rate£384,885
Stress-rate payment ceiling£318,346
Illustrative borrowing limit£270,000

Usable annual income = £60,000 + (£0 × 0%) = £60,000 + £0 = £60,000.

Deposit and property price

Total deposit, buying-cost reserve, illustrative borrowing and property price
Total deposit£40,000
Buying-cost reserve£5,000
Deposit toward property price£35,000
Illustrative mortgage borrowing£270,000
Illustrative property price£305,000
Illustrative loan to value88.5%

Monthly planning

Monthly income, costs, mortgage payment and remainder before and after your safety buffer, at the current and stress rate
Gross monthly household income equivalent£5,000.00
Existing monthly commitments£500.00
Essential household costs£1,500.00
Owner-only property costs£250.00
Mortgage payment, current rate£1,578.39
Remaining before safety buffer£1,171.61
Chosen safety buffer£500.00
Remaining after safety buffer£671.61
Mortgage payment, stress rate£1,908.30
Remaining before safety buffer, stress rate£841.70
Chosen safety buffer£500.00
Remaining after safety buffer, stress rate£341.70

Gross monthly income is annual household income divided by 12. It is not take-home pay and does not include tax, National Insurance, pension, Student Loan or other payroll deductions.

Enter a property price above under "Test a property price" to see the mortgage, deposit percentage and payments it would imply.

How mortgage-rate assumptions change the payment

Scenarios built from the rates you entered, not a forecast of future rates.

Monthly payment and remaining amount for the illustrative borrowing limit at the current rate, current rate plus one percentage point, and the stress rate
ScenarioRateMonthly paymentRemaining after costs and buffer
Current rate5%£1,578.39£671.61
Current rate + 1 percentage point6%£1,739.61£510.39
Stress rate7%£1,908.30£341.70

How to use this calculator

  1. Enter your household income. Choose "Joint application" if a second applicant's income should count, and set the share of any variable income you want included.
  2. Enter your total deposit and a buying-cost reserve — either a quick total or itemised costs such as Stamp Duty/Land Tax, legal fees and surveys — so the calculator can work out the deposit left toward a property price.
  3. Enter your existing monthly commitments and essential household costs, either as a quick total or itemised.
  4. Enter any owner-only monthly costs you expect, such as buildings insurance, a service charge or maintenance — without double counting a cost already entered above.
  5. Set your mortgage rate, term, stress-test rate, indicative income multiple and monthly safety buffer.
  6. Read the illustrative borrowing limit and property-price range below, and optionally test a specific property price.

Results update as you change any figure. Use Reset to return to the worked example.

How does this calculator work?

This calculator works out two independent borrowing ceilings and uses the lower of the two as your illustrative borrowing limit. The first ceiling applies your chosen income multiple to your usable annual household income. The second ceiling works out the largest loan that a standard repayment mortgage, at your stress-test rate and chosen term, could be repaid from your monthly payment budget — what is left of your gross monthly income after your entered commitments, essential costs, owner-only costs and safety buffer.

usable annual income = basic1 + (variable1 × included1) + basic2 + (variable2 × included2)
  • basic1/basic2 — each applicant's basic annual income
  • variable1/variable2 — each applicant's variable annual income
  • included1/included2 — the share of variable income you choose to include, 0% to 100%
income-multiple ceiling = usable annual income × indicative income multiple
monthly payment budget = gross monthly income − commitments − essential costs − owner costs − safety buffer
monthly mortgage payment = L × r(1+r)ⁿ ÷ [(1+r)ⁿ − 1]
  • L — the loan amount
  • r — the annual interest rate divided by 12
  • n — the mortgage term in months
  • The stress-rate payment ceiling is the largest loan whose payment, at the stress rate, does not exceed your monthly payment budget — the inverse of this same formula

Your illustrative borrowing limit is the lower of the income-multiple ceiling and the stress-rate payment ceiling. Your illustrative property price adds your usable deposit — your total deposit minus any buying-cost reserve you set aside — to that borrowing limit. For example, with a single £60,000 basic income, no variable income, a £40,000 deposit, a £5,000 buying-cost reserve, £500 of monthly commitments, £1,500 of essential costs, £250 of owner-only costs, a 25-year term, a 5% mortgage rate, a 7% stress rate, a 4.5× income multiple and a £500 safety buffer, the monthly payment budget is £2,250 and the income-multiple ceiling is £270,000 — the calculator reports whichever of the income-multiple and stress-payment ceilings is lower as the illustrative borrowing limit, then adds the £35,000 usable deposit to reach an illustrative property price.

What does this calculator assume, and what are its limits?

  • Income is gross — before tax, National Insurance, pension contributions, Student Loan repayments and other payroll deductions. For an after-tax estimate, see the UK Take-Home Pay Calculator.
  • Every cost, rate, term and multiple in this illustration is a figure you entered yourself; none are looked up or verified.
  • This calculator does not calculate Stamp Duty Land Tax, other purchase taxes, or any location-specific rule automatically — see the UK Stamp Duty Calculator for that.
  • It does not check, estimate or predict credit history, lender eligibility, product availability or mortgage approval.
  • It does not forecast future interest rates, house prices or your income — the stress rate and income multiple are planning assumptions you choose, not a market prediction.
  • This is not a mortgage offer, lending decision, affordability assessment, financial advice, mortgage advice, tax advice or legal advice. If you are still deciding whether to rent or buy at all, see the Rent vs Buy Calculator.

Important information

Important: This calculator is a planning illustration, not a mortgage offer, lending decision or affordability assessment. Mortgage lenders use their own criteria and may verify income, review credit commitments, assess household spending, consider future changes and test whether payments remain manageable if interest rates rise.

Frequently asked questions

How much mortgage can I afford in the UK?

There is no single answer, because lenders use their own income treatment, spending assumptions, stress tests and credit criteria. This calculator gives an illustrative range by applying an income multiple you choose and a stress-rate payment test to your usable income and entered monthly costs, then reporting the lower of the two as the illustrative borrowing limit. It is a planning starting point, not a lending decision.

Is 4.5 times income enough to estimate a mortgage?

4.5× is a commonly cited planning multiple, and it is this calculator's default, but it is not a rule any specific lender applies. Many lenders use different multiples depending on income level, deposit size, credit history and other factors. You can change the "Indicative income multiple" field to any value from just above 0 up to 10 to see how it affects the result.

Why does this calculator use a stress interest rate?

A stress rate tests whether the payment would still look manageable at a higher interest rate than you are currently offered. UK mortgage lenders commonly run a similar check as part of their own affordability assessment, though the exact method and rate they use vary and are not disclosed by this calculator. Entering a stress rate above your mortgage rate lets you see a second borrowing ceiling based on that higher payment.

Does this show whether I will be approved for a mortgage?

No. This calculator does not assess, predict or estimate mortgage approval, lender eligibility or credit-check outcomes. It produces an illustrative range from the figures you enter. A lender assessment considers verified income, credit history, existing commitments, household spending, the specific property and other criteria this calculator does not have access to.

Should I include overtime, bonus, commission or self-employed income?

You can include a share of variable income using the "Variable income included" field. Lenders often treat variable, bonus, commission and self-employed income differently from basic salary — for example by averaging it over several years or only counting part of it — so this calculator lets you choose the share you want to test rather than assuming any lender's specific treatment.

What costs should I include besides the mortgage payment?

This calculator asks separately for existing monthly commitments (such as loans, car finance and credit-card minimums), essential monthly household costs (such as food, utilities and transport), and owner-only property costs (such as buildings insurance, service charge and maintenance). Keeping these separate, and avoiding entering the same cost — such as Council Tax — in more than one section, gives a more transparent monthly planning picture.

Does this include Stamp Duty and other buying costs?

This calculator does not calculate Stamp Duty Land Tax, legal fees, survey costs or any other buying cost automatically. You can enter a quick total or itemise these costs yourself as a "buying-cost reserve", which is set aside from your total deposit before the remaining usable deposit is applied toward a property price. For an automatic Stamp Duty Land Tax estimate, see the UK Stamp Duty Calculator.

Can I use this for a joint mortgage?

Yes. Choose "Joint application" under household income to enter a second applicant's basic and variable annual income. Both applicants' usable income is added together before the income multiple and stress-rate calculations are applied.

Why is the payment different at the stress rate?

The stress-rate payment is the standard mortgage repayment figure recalculated at your entered stress rate instead of your entered mortgage rate, for the same illustrative borrowing amount and term. A higher rate produces a higher monthly payment, which is why the "Remaining after safety buffer, stress rate" figure is usually lower than the equivalent figure at your current rate.

Is this based on gross or take-home income?

This calculator uses gross annual household income — income before tax, National Insurance, pension contributions, Student Loan repayments or other payroll deductions — divided by 12 to get a gross monthly income equivalent. It does not calculate take-home pay. For that, see the UK Take-Home Pay Calculator.