Mortgage Overpayment Calculator
See how much you could save by making extra mortgage payments
Last updated: February 2026
Current Mortgage
Overpayments
Annual: £2,400
Optional large payment now
Typical: 10% of balance per year
Total Interest Saved
£36,280
By making regular overpayments
Time Saved
6.1 years
73 months
Comparison
Without Overpayments
With Overpayments
Balance Over Time
Interest Breakdown
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.
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