Mortgage Calculator for the United Kingdom Stamp Duty, BoE stress tests, fixed vs tracker rates, and ERC-aware prepayments.

SDLT is a progressive tax. For standard buyers in England, the first £250,000 is tax-free, then 5% on £250,001–£925,000, 10% on £925,001–£1.5M, and 12% above £1.5M. First-time buyers get 0% on the first £425,000 for properties up to £625,000. An extra 5% surcharge applies to additional properties.

The Bank of England requires lenders to stress test your ability to repay at the Standard Variable Rate (SVR) plus 3%. If your lender's SVR is 7.5%, you need to qualify at 10.5%. This ensures you can still afford payments if rates rise.

Most UK lenders require at least 5% deposit (95% LTV). A 10% deposit (90% LTV) gives access to better rates, and 15-20%+ unlocks the most competitive deals. Help to Buy ISAs can supplement your deposit savings.

A fixed rate locks your interest for a set period (typically 2-5 years). A tracker rate follows the Bank of England base rate plus a fixed margin. The SVR (Standard Variable Rate) is the lender's default rate, usually the most expensive option. We compare all three in our Rate Comparison tool.

Most UK fixed-rate deals allow overpayments of up to 10% of your outstanding balance each year without penalty. Overpaying beyond this triggers Early Repayment Charges (ERCs), typically 5% in year 1, decreasing to 1% by year 5. Our Prepayment Simulator models these charges.

Yes. All our calculators and comparison tools are completely free. No account required, no tracking, no hidden fees. We believe UK homebuyers deserve straightforward access to mortgage math.