Buy-to-Let Mortgage Calculator UK
Buy-to-let mortgage calculator UK: test rental coverage using assumptions you can see and change, including an illustrative interest-only stress calculation.
Set your buy-to-let assumptions
The default 5.5% stress rate and 125% ICR are examples only. Lenders set their own criteria and can use different rates, ICRs and affordability checks.
How this buy-to-let check works
Instead of treating one ICR as universal, this page makes both the stress rate and ICR visible and editable. The rent-supported loan uses an interest-only stress calculation: annual rent divided by the ICR requirement and stress rate. It is a planning illustration, not a lender decision.
Sources and limits
There is no single statutory buy-to-let ICR or stress rate. Lender criteria vary by tax status, product, borrower type, property and market conditions. Consider voids, repairs, agent fees, insurance, tax and regulatory costs separately.