Loan Calculator UK: monthly repayments and interest
Work out the monthly payment and total cost of a loan from the amount, interest rate and term.
Estimates for information only, using 2026/27 rates for England, Wales and Northern Ireland unless stated. Not financial or tax advice; check your own situation with HMRC or a qualified adviser.
How it works
We use the standard amortising loan formula, the same one lenders use for fixed-rate loans.
The APR includes some fees, so using the APR gives a closer estimate of the true cost.
Total interest = (monthly payment Γ number of months) β amount borrowed.
Frequently asked questions
Is a longer loan term cheaper?+
Monthly payments are lower, but you pay more interest overall.
What's the difference between APR and interest rate?+
APR includes the interest rate plus certain fees, giving a fairer comparison between loans.