Buy To Let Mortgage Calculator
Calculate your buy to let mortgage instantly. Free, accurate tool showing monthly payments, rental yield, ICR stress test, and cash flow for landlords.
Calculate Your Buy To Let Mortgage
Enter your property value, deposit, mortgage rate and expected rent to see your monthly payment, rental yield, and whether your rent passes a typical lender ICR stress test.
Mortgage Details
Enter your figures to see your full BTL mortgage breakdown
BTL Mortgage Results
Your monthly payment, yield, and stress test outcome
Typical ICR Requirements
Interest Coverage Ratio requirements commonly used by UK buy to let lenders, which vary by borrower tax status.
| Borrower Type | Typical ICR | Typical Stress Rate |
|---|---|---|
| Basic-rate taxpayer, individual | 125% | 5.5% or pay rate + margin |
| Higher-rate taxpayer, individual | 145% | 5.5% or pay rate + margin |
| Limited company / SPV landlord | 125% | 5.5% or pay rate + margin |
| 5-year fixed rate product | 125–145% | Often pay rate (no extra stress) |
Buy To Let Calculator FAQ
Everything you need to know about buy to let mortgages, rental yield, and lender stress tests.
For an interest-only buy to let mortgage, the monthly payment is simply the loan amount multiplied by the annual interest rate, divided by 12. For a repayment mortgage, an amortisation formula is used that includes both interest and capital repayment over the mortgage term.
Gross rental yield is the annual rental income divided by the property’s purchase price or value, expressed as a percentage. It gives a quick measure of a property’s income return before costs such as mortgage interest, maintenance, and management fees are deducted.
The Interest Coverage Ratio (ICR) stress test is used by lenders to check that expected rental income comfortably covers mortgage interest, typically requiring rent to be at least 125 to 145 percent of the interest payment, often calculated at a higher ‘stressed’ interest rate for safety.
Many landlords choose interest-only buy to let mortgages because they keep monthly payments lower, with the capital typically repaid when the property is eventually sold or refinanced, though repayment mortgages are also available and reduce the loan balance over time.