Mortgage Overpayment Calculator

See how much you could save by making extra mortgage payments

Last updated: February 2026

Current Mortgage

£
%
Standard Monthly Payment£1,112

Overpayments

£

Annual: £2,400

£

Optional large payment now

%

Typical: 10% of balance per year

Annual Limit£20,000
Your Annual Total£2,400

Total Interest Saved

£36,280

By making regular overpayments

Time Saved

6.1 years

73 months

New Monthly Payment
£1,312
200 extra
Total Saved
£35,752
Interest + payments saved
New Term
18.9 yrs
Was 25 years

Comparison

Without Overpayments

Monthly Payment£1,112
Term25 years
Total Interest£133,499
Total Paid£333,499
Mortgage-Free DateMar 2051

With Overpayments

Monthly Payment£1,312
Term18.9 years
Total Interest£97,219
Total Paid£297,748
Mortgage-Free DateMar 2045

Balance Over Time

Year 1
£193,119
Year 2
£185,922
Year 3
£178,395
Year 4
£170,522
Year 5
£162,287
Year 6
£153,673
Year 7
£144,664
Year 8
£135,242
Year 9
£125,386
Year 10
£115,077

Interest Breakdown

Interest Without Overpayments£133,499
Interest With Overpayments£97,219
Interest Saved£36,280

Overpayment Benefits

  • • Save £36,280 in interest charges
  • • Become mortgage-free 6.1 years earlier
  • • Reduce monthly payment by remortgaging at lower balance
  • • Build equity faster for future flexibility
  • • Guaranteed return equal to your mortgage rate (4.5%)

Understanding Mortgage Overpayments

The Power of Overpaying

Every extra pound you pay goes directly toward reducing your mortgage balance, not interest. This reduces the amount of interest you pay over the mortgage term and can save you thousands.

Example:

£200,000 mortgage at 4.5% over 25 years: Standard cost = £111,100 in interest. Overpay £200/month and save £36,280while finishing 6.1 years early.

Calculator shows potential savings based on consistent overpayments. Always check your mortgage terms before overpaying.