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Family / Household Mortgage Affordability

Estimate how much a UK household can borrow on a residential mortgage given salaries, bonuses, dividends, rental income, dependents and existing debts. Combines the income-multiple rule (4.5×) with a debt-service affordability stress test at the contract rate + 1 %.

Income (annual gross unless noted)

Household & Liabilities

Mortgage Product

Estimated max property price

£387,500

Borrow up to £337,500 + your £50,000 deposit at 87 % LTV. Monthly repayment at 4.5% over 30 years: £1,710.

How each rule scores it

Lower of the two — your indicative ceiling

£337,500

Income & debt summary

Counted annual income (after lender weights)

£75,000

Counted monthly income

£6,250

Per-dependent allowance

− £0

Max monthly mortgage payment supported

£2,188

Indicative only. Actual lender decisions depend on credit score, employment status, income proof history (typically 2 years for self-employed / dividends), property type and product fees. Speak to a broker for exact figures.

What is the Family / Household Mortgage Affordability?

Mortgage affordability for a UK household is the maximum loan a lender will offer based on counted income (salary, weighted bonus, dividends, rental), existing debts and dependents. Most lenders apply a 4.5× income multiple alongside an affordability stress test of the contract rate + 1%, then take the lower figure.

Last reviewed: against HMRC rates for 2024/25 & 2025/26.

Typical UK lender affordability inputs

Income multipleStandard household4.5× (some 5×–5.5× for higher earners)
Stress rateAffordability testPay rate + 1% (legacy FCA buffer)
Bonus / commissionCounted income50% (lender-dependent: 0–100%)
Rental income (residential application)Counted income75% (allows for voids and costs)
Per-dependent allowanceAffordability deduction~£250/child/month

Worked example

A couple earning £45k + £30k = £75k counted income can borrow ~£337,500 on the 4.5× multiple. With a £50k deposit that supports a property up to ~£387,500 — assuming the affordability stress test at the contract rate + 1% doesn't bring it down further.

Frequently asked questions

+How much can I borrow on a £75,000 household income?

Most lenders cap residential lending at 4.5× of qualifying income — about £337,500. Some stretch to 5–5.5× for higher earners, certain professions, or with longer terms. Affordability stress tests can reduce this further if you have significant debts or dependents.

+Does rental income count for a residential mortgage?

Yes — typically 75% of gross rent is added to your counted income, the haircut allowing for voids and running costs. Some lenders use 100% if you can show 2 years of consistent rental history.

+Will dependents reduce my mortgage?

Yes. Lenders deduct around £250 per child per month from disposable income before calculating the maximum payment. A second or third child noticeably reduces affordability — even on the same income.

+How is bonus or commission income treated?

Most lenders count 50% of bonus/commission, averaged over 2–3 years of payslips/P60s. A handful count 100%; others count 0% if the bonus is irregular. It pays to bank with a lender that recognises your earning pattern.

+What's the difference between the income multiple and affordability rules?

Income multiple is a hard cap (e.g. 4.5×). Affordability is a stress test — it back-solves the loan from how much monthly payment your post-debt, post-dependent income can sustain at the contract rate + 1%. Lenders apply the lower of the two.