Amortisation Schedule Calculator
See your full repayment schedule, overpayment savings, and payoff date.
Instalment
£1,389.58
Total Interest
£166,874.36
Total Cost
£416,874.36
APR (APR)
4.50%
| Period | Instalment | Interest | Loan Amount | Balance |
|---|---|---|---|---|
| 1 | £11,136.70 | £5,538.27 | £244,461.73 | |
| 2 | £10,882.27 | £5,792.70 | £238,669.02 | |
| 3 | £10,616.16 | £6,058.82 | £232,610.20 | |
| 4 | £10,337.82 | £6,337.16 | £226,273.05 | |
| 5 | £10,046.69 | £6,628.29 | £219,644.76 | |
| 6 | £9,742.18 | £6,932.79 | £212,711.97 | |
| 7 | £9,423.69 | £7,251.28 | £205,460.69 | |
| 8 | £9,090.57 | £7,584.40 | £197,876.29 | |
| 9 | £8,742.15 | £7,932.83 | £189,943.46 | |
| 10 | £8,377.71 | £8,297.26 | £181,646.19 | |
| 11 | £7,996.54 | £8,678.44 | £172,967.76 | |
| 12 | £7,597.85 | £9,077.12 | £163,890.63 | |
| 13 | £7,180.85 | £9,494.12 | £154,396.51 | |
| 14 | £6,744.69 | £9,930.28 | £144,466.23 | |
| 15 | £6,288.50 | £10,386.48 | £134,079.75 | |
| 16 | £5,811.34 | £10,863.63 | £123,216.12 | |
| 17 | £5,312.27 | £11,362.70 | £111,853.41 | |
| 18 | £4,790.27 | £11,884.70 | £99,968.71 | |
| 19 | £4,244.29 | £12,430.69 | £87,538.02 | |
| 20 | £3,673.22 | £13,001.75 | £74,536.27 | |
| 21 | £3,075.93 | £13,599.05 | £60,937.23 | |
| 22 | £2,451.19 | £14,223.79 | £46,713.44 | |
| 23 | £1,797.75 | £14,877.22 | £31,836.22 | |
| 24 | £1,114.29 | £15,560.68 | £16,275.54 | |
| 25 | £399.44 | £16,275.54 | £0.00 |
Compare Methods
Equal Instalment (Repayment)
Instalment
£1,389.58
Total Interest
£166,874.36
Interest Only
Instalment
£937.50
Total Interest
£843,750.00
An amortisation schedule breaks every mortgage or loan payment down into two parts: the interest charged on what you still owe, and the capital (principal) that actually reduces your debt. UK lenders quote both a headline interest rate and an Annual Percentage Rate of Charge (APR), but neither figure alone tells you how much of each monthly payment clears the balance — that's what the schedule below shows, month by month, for the whole term.
Most UK mortgages and loans use the standard repayment method: one fixed monthly instalment for the whole term, with the interest share falling and the capital share rising as the balance comes down. This tool lets you see that split, model an overpayment, and compare shortening the term against lowering the payment — the two ways a lender can apply extra money you send in.
How the Interest and Capital Split Changes Every Month
Interest is calculated on the outstanding balance for that period, so the amount you still owe drives the interest charge — not the size of your original loan. Early in a 25-year mortgage, most of the payment services interest; by the final years, almost all of it comes off the balance.
UK mortgage interest is typically calculated daily on the outstanding balance and charged to the account monthly, so the exact date a payment lands can shift the split very slightly from month to month — the schedule above uses standard monthly compounding for clarity.
Overpayments: Shorten the Term or Lower the Payment
Most UK lenders let you overpay up to 10% of the outstanding balance each year without an Early Repayment Charge (ERC) — check your mortgage offer for the exact allowance. Beyond that, or during a fixed-rate period, an ERC typically tapers from around 5% down to 1% the closer you get to the end of the deal.
You can apply an overpayment two ways: keep the term the same and ask for a lower monthly payment, or keep the payment the same and finish early. Ending early saves more interest overall, because the balance — and therefore the interest charged on it — falls faster.
Fixed-Rate Deals and What Happens When Yours Ends
Most UK mortgages are fixed for 2 or 5 years and then revert to the lender's Standard Variable Rate (SVR) unless you remortgage. Because this schedule is quoted at a single fixed rate, re-run it with your likely SVR or new fixed rate as the deal end approaches, to see how the payment will actually change.
Worked Example: £250,000 Over 25 Years at 4.5%
On a £250,000 repayment mortgage at 4.5% over 25 years, the monthly payment is £1,389.58.
Over the full 300 payments you would pay £166,874.36 in interest, for a total repayment of £416,874.36.
In month one, roughly £938 of that payment is interest and only about £452 reduces the balance; by year 20 the split has essentially reversed.
Payment = P × [r(1+r)^n] / [(1+r)^n − 1], where P = loan amount, r = monthly interest rate, n = number of monthly payments
Repayment vs Interest-Only Mortgages
This calculator models a standard repayment mortgage, where every payment reduces the balance to zero by the end of the term. An interest-only mortgage instead keeps the balance unchanged and pays only interest each month — you then need a separate plan (savings, investments, or sale of the property) to clear the capital at the end. Compare both using the method switch above before deciding which suits your circumstances.
Early Repayment Charges Explained
Unlike EU consumer credit, UK Early Repayment Charges are not capped by statute — each lender sets its own tapering scale in the mortgage offer, commonly starting around 5% in year one and falling by roughly one percentage point a year. The FCA's MCOB 11 rules require the charge to be fair and disclosed upfront, but do not fix a maximum percentage.
Most deals also include a fee-free overpayment allowance, typically 10% of the balance per year, so modest overpayments rarely trigger a charge — it is large lump sums or full early redemption during the fixed period that are affected.
Frequently Asked Questions
Why is most of my mortgage payment interest at the start?
Interest is charged on the outstanding balance, which is at its highest right at the start of the mortgage. As you pay down the capital each month, the balance — and therefore the interest charged on it — falls, so a growing share of each fixed payment goes toward capital instead.
How much can I overpay my mortgage without a penalty?
Most UK lenders allow overpayments of up to 10% of the outstanding balance per calendar year without an Early Repayment Charge, though some cap it lower or higher — check your mortgage offer document. Overpaying beyond that allowance during a fixed-rate period usually triggers the ERC.
Should I shorten my mortgage term or lower my monthly payment?
Shortening the term while keeping payments the same saves more interest overall, because the balance falls faster. Lowering the payment instead reduces monthly outgoings, but the mortgage runs its full original length — useful if you need the cash flow rather than the long-term saving.
What is a mortgage repayment schedule?
A repayment schedule (or amortisation schedule) lists every payment for the life of the mortgage, showing how much of each goes to interest and how much reduces the capital, plus the balance remaining after each payment.
How is UK mortgage interest actually calculated?
Most UK mortgages accrue interest daily on the outstanding balance, then charge the accrued interest to the account monthly. This calculator uses standard monthly compounding, which is accurate to within a few pounds of the daily-interest figure your lender will show.
What happens to my payment when my fixed rate ends?
Unless you remortgage or switch to a new fixed deal, your mortgage reverts to the lender's Standard Variable Rate (SVR), which is usually higher. Re-run this calculator with your expected SVR (or new fixed rate) and remaining term to see the new payment.
Is there a fee for repaying my mortgage in full early?
If you're still within a fixed-rate or discount period, repaying in full usually triggers the Early Repayment Charge set out in your mortgage offer. Once you're on the lender's standard variable rate, you can normally repay in full at any time with no charge.
Can I switch between interest-only and repayment?
Most lenders allow a switch, subject to affordability checks, though moving from interest-only to repayment raises your monthly payment since you are now also paying down capital. Speak to your lender or a mortgage adviser before switching.
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