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Mortgages & property

Compare two mortgages — total cost calculator

The headline rate is only part of the story. Comparing two mortgages properly means looking at the total cost — monthly payment, product fee and the balance left at the end of the initial deal period.

Mortgage A
Mortgage B

Mortgage B is cheaper by £286.41 over 2 years.

Compared over the shorter of the two deal lengths (2 years) so you are comparing like with like.

A monthly payment
£1,250.43
A total cost over 2yr
£31,009
A balance at end
£241,591
B monthly payment
£1,280.12
B total cost over 2yr
£30,723
B balance at end
£241,875
A: total payments + fee£31,009
A: interest paid in period£21,602
B: total payments + fee£30,723
B: interest paid in period£22,598
Difference over the comparison period£286.41

Total cost includes monthly payments over the initial deal plus the product fee paid upfront. The headline rate alone can be misleading when fees differ — always compare like-with-like over the same number of years.

How it works

  1. We compute the monthly payment for each deal over your chosen term using the standard amortisation formula.
  2. We then total all payments over the shorter of the two initial deal lengths so the comparison is like-with-like, and add the product fee on top.
  3. We also show the balance remaining at the end of the period — useful when remortgaging because that is the figure you will refinance.

Common questions

Should I always pick the lower total cost?
Not necessarily. A 5-year fix gives you certainty against rate rises but is usually more expensive on paper than a 2-year fix if rates fall. Cost is only one factor.
Why is the balance at the end different?
A higher rate means more of each payment is interest, so less of the balance is paid down. Over a 2-year period the difference can easily be £2,000–£5,000.
Does this include valuation, legal and broker fees?
No. Those are usually one-offs that depend on the lender's incentives (free valuation, free legals on remortgage). Add them on top when comparing real-world costs.

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