A £400,000 mortgage requires a minimum income of £88,889 at the standard 4.5× multiple — individually or combined. Common joint income combinations that qualify: £55,000 + £34,000, £60,000 + £29,000, or £50,000 + £39,000. As a sole borrower, a salary of at least £80,000–£89,000 is needed depending on the lender. Monthly repayments at 4.5% over 25 years are £2,222/month. The monthly payment represents approximately 30% of net income for a household earning £89,000 combined — manageable but meaningful.
£400k mortgage affordability calculator
Income required for a £400k mortgage — by multiple
UK lenders use income multiples as a primary affordability filter. The table below shows the income required to reach £400,000 at each multiple, who typically offers it, and what the monthly payment looks like at mid-2025 rates.
| Multiple | Sole income needed | Joint income example | Lender type | Monthly payment (4.5%, 25yr) |
|---|---|---|---|---|
| 4.0× (cautious) | £100,000 | £65k + £35k | Cautious or high-LTV lenders | £2,222 |
| 4.5× (standard) | £88,889 | £55k + £34k | All mainstream lenders | £2,222 |
| 4.75× | £84,211 | £52k + £32k | Some lenders for clean profiles | £2,222 |
| 5.0× (professional) | £80,000 | £50k + £30k | Professional mortgage products | £2,222 |
| 5.5× (specialist) | £72,727 | £45k + £28k | Specialist lenders, low LTV | £2,222 |
The monthly payment is the same regardless of income multiple — £2,222 at 4.5% over 25 years. The multiple only determines whether the lender will approve the loan. Higher multiples require a stronger qualifying profile: low LTV, excellent credit, stable employment, and in some cases a qualifying professional occupation.
Joint income combinations that qualify for a £400k mortgage
Most £400k mortgages are obtained on joint applications. The table below shows common real-world income combinations and whether they meet standard 4.5× criteria.
| Income 1 | Income 2 | Combined | Max mortgage (4.5×) | vs £400k |
|---|---|---|---|---|
| £50,000 | £25,000 | £75,000 | £337,500 | £62,500 short |
| £55,000 | £30,000 | £85,000 | £382,500 | £17,500 short |
| £55,000 | £34,000 | £89,000 | £400,500 | ✓ Meets target |
| £60,000 | £30,000 | £90,000 | £405,000 | ✓ Meets target |
| £65,000 | £25,000 | £90,000 | £405,000 | ✓ Meets target |
| £70,000 | £20,000 | £90,000 | £405,000 | ✓ Meets target |
| £89,000 | £0 (sole) | £89,000 | £400,500 | ✓ Meets target (sole) |
| £80,000 | £0 (sole) | £80,000 | £360,000 (5× = £400k) | ✓ Via professional mortgage |
Green = meets £400k standard criteria. Yellow = close — a specialist product or 5× income may bridge the gap. The bottom row shows that a sole borrower on £80,000 reaches £400,000 via a professional mortgage product at 5× income, though this requires qualifying professional status and typically lower LTV.
Monthly repayments on a £400,000 mortgage — all key rates
The monthly payment depends on your interest rate and term length. The panels below show 25-year repayment payments at the most common 2025 rate levels.
The difference between 4.0% and 5.5% on a £400,000 mortgage is £349/month — or £20,940 over a five-year fixed period. At this loan size the rate you secure matters considerably. A whole-of-market broker who identifies a rate 0.3% below what a direct lender offers saves approximately £4,200 over five years on this balance.
Term length impact — £400k at 4.5%
| Term | Monthly payment | Total repaid | Total interest | Extra vs 20yr |
|---|---|---|---|---|
| 20 years | £2,531 | £607,440 | £207,440 | — |
| 25 years | £2,222 | £666,600 | £266,600 | +£59,160 interest |
| 30 years | £2,027 | £729,720 | £329,720 | +£122,280 interest |
| 35 years | £1,893 | £794,060 | £394,060 | +£186,620 interest |
Each 5-year term extension saves approximately £129–£309/month but adds £59,000–£187,000 in total interest. The 25-year term is most common; extend only if the lower monthly payment is genuinely needed to pass affordability or maintain financial headroom.
Deposit thresholds for a £400k mortgage
| LTV | Deposit % | Property value | Deposit needed | Typical rate (2025) |
|---|---|---|---|---|
| 90% | 10% | £444,444 | £44,444 | ~4.85% |
| 85% | 15% | £470,588 | £70,588 | ~4.6% |
| 80% | 20% | £500,000 | £100,000 | ~4.45% |
| 75% | 25% | £533,333 | £133,333 | ~4.35% |
| 60% | 40% | £666,667 | £266,667 | ~4.1% |
Moving from 90% to 85% LTV on a £400k mortgage saves approximately £80–£100/month through a lower rate — worth £4,800–£6,000 over a 5-year fix. The property value and deposit in each row are those needed to result in exactly a £400k mortgage at that LTV.
Three real scenarios — who can afford a £400k mortgage?
Priya earns £56,000 as a marketing manager and James earns £35,000 as a secondary school teacher. Combined £91,000. They have saved £55,000 over four years and want to buy a two-bed flat in Walthamstow, London (Zone 3).
| Property price | £455,000 |
| Deposit (12.1%) | £55,000 |
| Mortgage needed | £400,000 |
| Income multiple | 4.40× combined — within standard limits |
| Monthly payment (4.5%, 25yr) | £2,222/month |
| As % of combined net income (~£5,860/mo) | 37.9% — manageable for London |
| Stamp duty (FTB — 5% on £155k above £300k) | £7,750 |
Dr Aisha earns £95,000 as a hospital consultant. She has saved £72,000 and is buying a three-bed house in the Midlands for £475,000.
| Property price | £475,000 |
| Deposit (15.2%) | £72,000 |
| Mortgage needed | £403,000 (≈£400k) |
| Income multiple | 4.24× — within standard limits |
| Monthly payment (4.4%, 25yr) | £2,196/month |
| As % of estimated net income (~£5,200/mo) | 42.2% — stretched but manageable |
| Stamp duty (FTB — 5% on £175k above £300k) | £8,750 |
At 4.24× income Dr Aisha is well within standard limits. Her 15.2% deposit gives 85% LTV, unlocking a competitive rate. The 42% payment-to-income ratio is at the upper end of comfortable for a sole buyer, but her income trajectory as a consultant — likely rising over time — gives confidence that affordability will improve.
Marcus earns £72,000 as a senior engineer. He has saved £80,000 (a large deposit relative to income) and wants to buy a property for £475,000.
| Property price | £475,000 |
| Deposit (16.8%) | £80,000 |
| Mortgage needed | £395,000 (≈£400k) |
| Income multiple at standard 4.5× | 5.49× — above standard cap |
| At professional/specialist 5.5× | £396,000 — just achievable |
| Monthly payment (4.5%, 25yr) | £2,194/month |
| As % of estimated net income (~£4,150/mo) | 52.9% — very stretched |
Marcus is right at the boundary of specialist lending — the income multiple required (5.49×) exceeds the standard 4.5× but just falls within some specialist lenders' 5.5× maximum. However, even if approved, the 52.9% payment-to-income ratio is genuinely challenging — leaving less than £2,000/month for all other living costs. A broker would likely advise reducing the target mortgage size or waiting for either salary growth or a larger deposit to improve the position.
Frequently asked questions
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How much income do you need for a £400,000 mortgage?At the standard 4.5× income multiple, a minimum income of £88,889 — individually or combined — is required for a £400,000 mortgage. Common joint income combinations include £55,000 + £34,000 or £60,000 + £30,000. As a sole borrower, professional mortgage products at 5× income reduce the threshold to £80,000. The monthly repayment at 4.5% over 25 years is £2,222 — approximately 30% of the net income of a household earning £89,000.
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Can I get a £400k mortgage on a single income?Yes, on a sufficiently high sole income. At standard 4.5× terms you need £88,889 gross salary. Professional mortgage products at 5× reduce this to £80,000. Specialist products at 5.5× reduce it further to £72,727. Below £72,000 as a sole borrower, a £400,000 mortgage is not achievable without a very large deposit to reduce the required loan below what income supports.
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What are the monthly repayments on a £400k mortgage?At 4.5% over 25 years — typical for mid-2025 — monthly repayments on £400,000 are approximately £2,222. At 5% over 25 years they rise to £2,338. Over 30 years at 4.5% they fall to £2,027. Use the calculator above for your specific rate and term. Total interest at 4.5% over 25 years is approximately £266,600 — so total repaid is approximately £666,600.
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What deposit do I need for a £400k mortgage?The deposit depends on the property value. At 90% LTV (10% deposit) the property is £444,444 and the deposit is £44,444. At 85% LTV (15%) the property is £470,588 and the deposit is £70,588. A larger deposit unlocks a better rate — moving from 90% to 85% LTV saves approximately £80–£100/month on a £400k mortgage through a lower interest rate.
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What is a comfortable payment-to-income ratio for a £400k mortgage?A monthly mortgage payment of no more than 35–40% of net income is generally considered sustainable. The £2,222/month payment on a £400k mortgage at 4.5% represents 35% of a net income of approximately £6,350/month — consistent with a combined gross income of approximately £100,000. At the minimum qualifying income of £88,889, the payment represents approximately 38% of net income — at the upper edge of comfortable. Budget carefully for maintenance, insurance, and other costs on top of the mortgage.
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