UK Mortgage Calculator — Payments & Stamp Duty
Model a repayment or interest-only mortgage and see your full Stamp Duty Land Tax bill in one place — including first-time buyer relief.
0% to £250k
SDLT BAND 1
5% to £925k
SDLT BAND 2
10% to £1.5m
SDLT BAND 3
12% above
SDLT BAND 4
🇬🇧 UK Mortgage
Repayment / Interest-Only · Stamp Duty
Monthly Payment
£1,804.94
Capital & interest
£315,000
Loan Amount
£5,000
Stamp Duty
£546,482
Total Cost
🏛️ Stamp Duty Land Tax (SDLT) Breakdown
Illustrative England/NI residential bands — always confirm current rates at gov.uk.
| Band | Rate | Taxable | Tax |
|---|---|---|---|
| £0 – £250,000 | 0% | £250,000 | £0 |
| £250,000 – £925,000 | 5% | £100,000 | £5,000 |
📅 Payment Schedule
| Period | Payment | Principal | Interest | Balance |
|---|---|---|---|---|
| Year 1 | £21,659 | £6,685 | £14,974 | £308,315 |
| Year 2 | £21,659 | £7,013 | £14,646 | £301,302 |
| Year 3 | £21,659 | £7,357 | £14,302 | £293,945 |
| Year 4 | £21,659 | £7,718 | £13,941 | £286,226 |
| Year 5 | £21,659 | £8,097 | £13,562 | £278,129 |
| Year 6 | £21,659 | £8,494 | £13,165 | £269,635 |
| Year 7 | £21,659 | £8,911 | £12,748 | £260,724 |
| Year 8 | £21,659 | £9,348 | £12,311 | £251,375 |
| Year 9 | £21,659 | £9,807 | £11,852 | £241,568 |
| Year 10 | £21,659 | £10,288 | £11,371 | £231,280 |
| Year 11 | £21,659 | £10,793 | £10,866 | £220,486 |
| Year 12 | £21,659 | £11,323 | £10,336 | £209,164 |
| Year 13 | £21,659 | £11,878 | £9,781 | £197,285 |
| Year 14 | £21,659 | £12,461 | £9,198 | £184,824 |
| Year 15 | £21,659 | £13,073 | £8,586 | £171,751 |
| Year 16 | £21,659 | £13,714 | £7,945 | £158,037 |
| Year 17 | £21,659 | £14,387 | £7,272 | £143,649 |
| Year 18 | £21,659 | £15,093 | £6,566 | £128,556 |
| Year 19 | £21,659 | £15,834 | £5,825 | £112,722 |
| Year 20 | £21,659 | £16,611 | £5,048 | £96,111 |
| Year 21 | £21,659 | £17,426 | £4,233 | £78,685 |
| Year 22 | £21,659 | £18,281 | £3,378 | £60,404 |
| Year 23 | £21,659 | £19,178 | £2,481 | £41,226 |
| Year 24 | £21,659 | £20,119 | £1,540 | £21,107 |
| Year 25 | £21,659 | £21,107 | £553 | £0 |
Understanding a UK Mortgage
🏠 Repayment Mortgages
The default choice for most residential buyers — every payment chips away at the balance, so the loan is guaranteed to be gone by the final month of the term.
📉 Interest-Only Mortgages
Lower monthly payments, but the capital doesn't shrink — lenders typically require proof of a credible repayment vehicle before approving one.
🏛️ Stamp Duty Bands
SDLT is progressive, like income tax — only the slice of the price inside each band gets that band's rate, not the entire purchase price.
🔑 First-Time Buyer Relief
A meaningfully bigger 0% band for qualifying first-time buyers — worth checking the box above if it applies, since it can save thousands.
— FAQ