£300,000 buy-to-let mortgage: payments and rent needed
What a £300,000 buy-to-let mortgage costs each month at different rates, and the rent you'd need to get it.
Key facts
- At 5%: £1,250 a month interest-only, £1,754 repayment (25 years).
- Rent needed (5.5% stress): about £1,719 (125%) or £1,994 (145%) a month.
- At 75% loan-to-value: a property of about £400,000.
- Lenders' stress rates and cover ratios vary; a broker can confirm.
Monthly payments on £300,000
At 5%, a £300,000 buy-to-let mortgage costs £1,250 a month interest-only, or £1,754 on a 25-year repayment basis. Every half-point on the rate changes the interest-only payment by £125 a month.
| Interest rate | Interest-only a month | Repayment (25 years) a month |
|---|---|---|
| 4% | £1,000 | £1,584 |
| 4.5% | £1,125 | £1,667 |
| 5% | £1,250 | £1,754 |
| 5.5% | £1,375 | £1,842 |
| 6% | £1,500 | £1,933 |
| 6.5% | £1,625 | £2,026 |
| 7% | £1,750 | £2,120 |
Rent needed to pass the lender test
Using a typical stress rate of 5.5%, lenders would want monthly rent of at least £1,719 at 125% cover (basic-rate taxpayers and companies) or £1,994 at 145% (higher-rate taxpayers). Lenders' figures vary.
| Rent cover | Minimum monthly rent | Minimum yearly rent |
|---|---|---|
| 125% | £1,719 | £20,625 |
| 145% | £1,994 | £23,925 |
Deposit and purchase price
At 75% loan-to-value, a £300,000 mortgage suits a property costing about £400,000, with a £100,000 deposit. Stamp Duty on that buy-to-let would be about £30,000 in England. See the Stamp Duty calculator.
Other loan sizes: £75k · £100k · £125k · £150k · £175k · £200k · £250k
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.