Mortgage Amortization Calculator
This mortgage amortization calculator shows how a fixed-rate loan is paid off over time. Enter the loan amount, the interest rate (APR) and the term in years, and it works out your monthly payment, the total interest you will pay and the total you will pay overall.
It also builds a year-by-year schedule showing how much of each payment goes towards principal and how much goes towards interest, and what balance remains. This helps you see how the loan balance falls over the life of the mortgage.
Year-by-year schedule
How to use the mortgage amortization calculator
- Enter the loan amount you plan to borrow in pounds (£).
- Enter the interest rate (APR) as a percentage.
- Enter the term of the loan in years.
- Read the monthly payment shown by the calculator.
- Check the total interest and total paid figures to see the full cost of the loan.
- Review the year-by-year schedule to see the principal, interest and remaining balance for each year.
The formula
- Monthly payment = P × r ÷ (1 − (1 + r) ^ −n), where P is the amount borrowed, r the annual rate ÷ 12 ÷ 100 and n the number of months
- Each month: interest = balance × annual rate ÷ 12; the rest of the payment reduces the balance
Worked example
The figures below are made up to show the maths. They are not current prices, rates or product figures.
| Loan amount | £300,000.00 |
|---|---|
| Interest rate (APR) | 6.5% |
| Term | 30 years |
- Monthly payment £1,896.20
- Total interest £382,633.47
- Total paid £682,633.47
Tips for an accurate answer
- Use the exact APR quoted in your mortgage offer, as this is the rate the calculator needs.
- Check that the loan amount matches the figure you are actually borrowing, after any deposit has been taken off the property price.
- Enter the term you have been offered rather than an estimate, because a shorter or longer term changes the payment noticeably.
- Confirm the final figures with your lender or bank before making any decisions, as this calculator is a guide based on the maths alone.
Questions people ask
How do I work out a simple monthly amortization?
Enter the loan amount, the interest rate (APR) and the term in years into the calculator. It will show your monthly payment, which stays the same for each month of the loan.
Can I use this mortgage amortization calculator for a UK mortgage?
Yes, the figures are shown in pounds (£) and the calculator works with a loan amount, an APR and a term in years. Confirm the final amounts with your lender, as they may include fees not shown here.
What does a mortgage amortization schedule show?
The schedule shows, year by year, how much of your payments goes towards principal and how much towards interest, along with the remaining balance. It helps you see how the loan reduces over time.
Is this amortization calculator free to use?
Yes, you can enter your loan amount, interest rate and term and see the results without any cost. Use the figures as a guide and check them with your lender before deciding.
What does this mortgage amortization calculator work out?
It works out your monthly payment, the total interest you will pay and the total amount paid over the term. It assumes a fixed interest rate and equal monthly payments throughout the loan.
What is an amortization schedule?
An amortization schedule is a table showing how each payment is split between interest and the repayment of the amount borrowed. The calculator shows this year by year, along with the balance still owed.
Why is most of the early payment interest?
Each month, interest is charged on the outstanding balance. Because the balance is highest at the start, more of the early payments go towards interest, and a smaller share reduces the balance.
Does the calculator include fees or insurance?
No. It only uses the loan amount, interest rate and term. Fees, insurance and any other charges from your lender are not included, so check these separately.
Sources
This calculator uses the standard loan and interest formulas above and the numbers you type. It needs no outside figures.
An estimate from the numbers you enter, worked out with the formula shown. It is maths, not financial advice: your lender or bank has the final figures. Page checked 23 Oct 2026. Read the disclaimer