£100,000 buy-to-let mortgage: payments and rent needed
What a £100,000 buy-to-let mortgage costs each month at different rates, and the rent you'd need to get it.
Key facts
- At 5%: £417 a month interest-only, £585 repayment (25 years).
- Rent needed (5.5% stress): about £573 (125%) or £665 (145%) a month.
- At 75% loan-to-value: a property of about £133,333.
- Lenders' stress rates and cover ratios vary; a broker can confirm.
Monthly payments on £100,000
At 5%, a £100,000 buy-to-let mortgage costs £417 a month interest-only, or £585 on a 25-year repayment basis. Every half-point on the rate changes the interest-only payment by £42 a month.
| Interest rate | Interest-only a month | Repayment (25 years) a month |
|---|---|---|
| 4% | £333 | £528 |
| 4.5% | £375 | £556 |
| 5% | £417 | £585 |
| 5.5% | £458 | £614 |
| 6% | £500 | £644 |
| 6.5% | £542 | £675 |
| 7% | £583 | £707 |
Rent needed to pass the lender test
Using a typical stress rate of 5.5%, lenders would want monthly rent of at least £573 at 125% cover (basic-rate taxpayers and companies) or £665 at 145% (higher-rate taxpayers). Lenders' figures vary.
| Rent cover | Minimum monthly rent | Minimum yearly rent |
|---|---|---|
| 125% | £573 | £6,875 |
| 145% | £665 | £7,975 |
Deposit and purchase price
At 75% loan-to-value, a £100,000 mortgage suits a property costing about £133,333, with a £33,333 deposit. Stamp Duty on that buy-to-let would be about £6,833 in England. See the Stamp Duty calculator.
Other loan sizes: £75k · £125k · £150k · £175k · £200k · £250k · £300k
Sources
- GOV.UK: Tax relief for residential landlords, how it's worked out
- GOV.UK: Stamp Duty Land Tax residential property rates
Sources last checked 10 November 2026. See all our sources and how we keep pages up to date.