Buy to Let Calculator
Work out the loan, monthly interest and yield on a buy to let.
Monthly profit before costs
£343.75
- Loan amount
- £165,000.00
- Monthly interest
- £756.25
- Gross yield
- 6%
Interest-only estimate before letting costs, maintenance and tax.
v1.0 · Reviewed September 2026
How this is worked out
The loan is price − deposit. Monthly interest is the loan × rate ÷ 12, and the profit line is rent less that interest. Gross yield is annual rent ÷ price.
Worked example
- Price £220,000
- Deposit £55,000
- Rate 5.5%
- Rent £1,100
loan £165,000, interest £756.25 a month
£343.75 a month before costs, at a 6% gross yield
Assumptions and limits
- Interest-only. A repayment mortgage costs more each month because it also pays down capital.
- Before letting fees, insurance, maintenance, safety certificates, service charges and void periods.
- Before tax. Individual landlords cannot deduct mortgage interest from rental income and instead receive a 20% tax credit, so the after-tax position is often materially worse than this figure suggests.