Mortgage Overpayment Calculator

See what overpaying could do for your mortgage.

Explore how making additional mortgage payments could affect your repayment timeline and the amount of interest you pay over the life of your mortgage.

Calculate Your Savings → Mortgage Guide
Overpayment impact Illustrative

Small extras can add up.

Compare your existing mortgage with a scenario where you make regular additional payments.

Potential interest saving £18,420
Original
Overpay
Interest
Overpayment Calculator

Compare your mortgage with regular overpayments.

Enter your current mortgage balance, interest rate, remaining term and proposed overpayment. The calculator provides an illustrative comparison of the potential interest saving and time reduction.

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Your mortgage details

Adjust the figures to compare different scenarios.
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This calculator provides an illustrative estimate only. Actual mortgage terms, early repayment charges, overpayment limits and lender rules can affect the outcome.

Potential interest saving £18,420
Illustrative comparison
Potential 2.8 years saved
Original monthly payment £1,461
Payment including overpayment £1,711
New estimated term 22.2 years
Current balance £250,000
Interest rate 5.00%
Monthly overpayment £250
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Compare before making extra payments

Check your mortgage terms and any applicable overpayment restrictions before changing your payments.

Continue Your Mortgage Research

Explore related mortgage guides and tools.

Once you understand the potential impact of overpayments, explore other useful mortgage topics before making a decision.

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Fixed-Rate Mortgage

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Remortgaging

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Mortgage Application

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Tracker Mortgage

Learn how tracker mortgages work and how their interest rates can move in relation to an underlying rate.

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Why can mortgage overpayments save interest?

Mortgage interest is generally calculated based on the outstanding balance. Paying additional amounts can reduce that balance sooner, which may reduce the amount of interest charged over time.

The exact benefit depends on your interest rate, remaining balance, mortgage term, payment structure and lender rules.

Things To Consider

An overpayment can be useful, but it is not automatically right for everyone.

Before making additional payments, consider your wider financial position and the terms attached to your mortgage.

01 Check whether your mortgage has an annual overpayment allowance or other restrictions.
02 Check whether an early repayment charge could apply to additional payments.
03 Consider whether keeping cash available as an emergency fund is more appropriate for your circumstances.
04 Compare the potential mortgage interest saving with other uses for the money.
Illustrative interest profile Potential saving
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Long-Term Impact

The value of an overpayment can build over time.

The earlier an additional payment reduces your mortgage balance, the longer that lower balance can affect future interest calculations. The effect depends on the structure and terms of your mortgage.

✓ Lower outstanding mortgage balance can reduce future interest charged.
✓ Regular overpayments can potentially shorten the overall repayment period.
✓ Even modest additional payments can be compared against your existing repayment strategy.
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Mortgage overpayment frequently asked questions
Frequently Asked Questions

Mortgage Overpayment FAQs

Common questions about mortgage overpayments, interest savings and repayment periods.

A mortgage overpayment is an additional payment made towards your outstanding mortgage balance on top of your normal scheduled repayment. Depending on the mortgage terms, overpayments may reduce the interest charged or shorten the repayment period.
It can. Reducing the outstanding mortgage balance earlier can reduce the amount on which interest is calculated. The actual saving depends on your mortgage rate, balance, term and lender's rules.
Some mortgages allow regular overpayments, while others may have annual limits or charges. Check your mortgage agreement or contact your lender to understand the applicable conditions.
Depending on the mortgage, an early repayment charge or other restriction may apply. Some mortgages also provide an annual overpayment allowance. Always check your specific mortgage terms before making a large additional payment.
There is no universal answer. The right choice depends on factors such as your mortgage rate, savings options, emergency fund, tax position, other financial priorities and any mortgage overpayment restrictions.
Not necessarily. The effect depends on how your lender applies overpayments. Some lenders reduce the term, while others may recalculate your future payments. Check how your mortgage provider handles additional payments.

See what an extra payment could mean for your mortgage.

Compare different overpayment scenarios and understand the potential impact before reviewing your mortgage terms.

Calculate Overpayment → Mortgage Calculator
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