EyeOnWhat this type of product does
A mortgage is a large loan repaid over many years, usually secured against the property itself. Offers combine several moving parts — interest rate, term, fees, rate type — and each part can be adjusted independently, which is why headline rates mislead.
Mortgage markets differ by country in tax relief, default rules and product structures. Nothing here recommends a product. The comparison below works on any set of offers from any market.
The numbers to line up side by side
Compare the total cost over the initial period, not the rate alone: rate plus arrangement fee, spread across the period the deal lasts, gives a fairer picture than either number alone. Some markets publish a standardised comparison rate for exactly this purpose; where one exists, read what it includes and excludes.
Check the rate type next. A fixed rate buys certainty for the deal period; a variable or adjustable rate may start cheaper and move with the market. The right choice depends on budget tolerance for change more than on forecasting rate movements, which even professionals get wrong.
Details that often hide in the small print
Early repayment charges are the detail that traps people: a low rate with a heavy exit fee can become expensive the year you need to move or remortgage. Check the length of any tie-in period, whether it outlasts the rate, and what overpayment is allowed each year without penalty.
Also compare what happens when the deal ends — the standard variable rate a deal reverts to can be several points above the market — and check fees for valuation, legal work and administration, some of which can be added to the loan and then earn interest for years.
A simple way to decide
Reduce the comparison to two numbers you can act on: the monthly payment and the total cost over the period you expect to hold the deal. Then test both against your budget with breathing room, because a mortgage that only works if nothing ever goes wrong is not affordable.
Run any offer through the mortgage repayment calculator, and check the deposit's effect on pricing with the loan-to-value calculator before accepting that the best-looking deal is the best deal for you.