Search
  1. Home
  2. Mortgages
  3. Mortgage Overpayment Calculator

Mortgage Overpayment Calculator

Use our mortgage overpayment calculator to work out the savings you could make by overpaying and how much faster your mortgage could be paid off.
+ 1 more

Many or all of the products and brands we promote and feature including our ‘Partner Spotlights’ are from our partners who compensate us. However, this does not influence our editorial opinion found in articles, reviews and our ‘Best’ tables. Our opinion is our own. Read more on our methodology here.

How much can I save by overpaying my mortgage?  

Overpaying on your mortgage could help you save money. It may also mean you can pay off your mortgage faster. 

Calculate what you could save and how much sooner you could clear your mortgage by overpaying regularly or making a lump sum payment. 

Effects of making overpayments

Making regular overpayments on your mortgage may save you a significant amount of money, find out how much with this mortgage overpayment calculator.


By regularly overpaying £200 per month we estimate that you will have

Saved £32,481.66 in interest

Cleared your mortgage balance 9 years 9 months earlier

Mortgage balance overtime

Balance remaining in undefined (with overpayment)

This information is an estimate and relies on certain assumptions. It is only intended as a general guide. Please ensure that you carefully check with your lender or brokers before proceeding with any mortgage overpayments.

Get £5 from Sprive to start your mortgage overpayment journey

Sprive is the free app helping homeowners pay off their mortgage faster and save thousands in interest. Track what you have saved and make one tap mortgage overpayments.

Download the app with code NERD5 and start saving on your mortgage

Ad Icon

How to calculate mortgage overpayments 

Our mortgage overpayment calculator estimates how much you could save, and how much quicker your mortgage could be paid off, by paying more towards your mortgage. You’ll need to enter the following details in the calculator to get an estimate:

Note that the figures the NerdWallet overpayment calculator provides are estimates based on the assumption your mortgage rate is unchanged for the duration of your mortgage – this isn’t likely to be the case in practice. Always check with your lender if there are limits and charges associated with overpaying before you pay extra – this is likely when you are within a deal period with your lender. 

What is a mortgage overpayment?

A mortgage overpayment is any additional money you pay towards your mortgage above your agreed monthly repayments. Mortgage overpayments can usually be made by lump sum or by increasing your regular monthly repayments. 

Should I overpay my mortgage monthly or by lump sum?

Making a bigger one-off lump sum overpayment will reduce your outstanding mortgage faster than smaller regular overpayments, saving more interest. 

However, once you’ve paid money into a mortgage, you may not be able to get it back. So if you don’t have savings set aside, or your budget is relatively tight, you may wish to be more cautious and opt for smaller monthly overpayments, which you can change or stop if necessary, 

How much can I overpay on my mortgage?

Some mortgages have limits on how much you can overpay without incurring a charge and some don’t. If you have a tracker mortgage or are paying your lender’s standard variable rate (SVR), you may be allowed to overpay as much as you like penalty-free. 

However, with fixed-rate mortgages, you’ll generally find overpayments are limited to 10% of your outstanding mortgage balance each year, or sometimes 20%. 

Overpay by more than you’re allowed and early repayment charges must be paid. These can be significant, so it’s important to check with your lender exactly how much extra can be paid without being charged. 

What are the advantages of making mortgage overpayments? 

Some of the advantages of making mortgage overpayments include:

» MORE: See current mortgage rates

What are the disadvantages of overpaying your mortgage?

There are some important things to consider before making mortgage overpayments, including: 

Should I overpay my mortgage?

Whether mortgage overpayments are the right option for you will depend on your financial circumstances. While paying more towards your mortgage could help you pay off your mortgage faster and reduce interest, it’s important to have sufficient savings set aside and not overstretch yourself financially. Speaking to your lender and getting mortgage advice may help you decide.

» MORE: Is it worth overpaying your mortgage?

Find the right mortgage deal

NerdWallet has partnered with L&C, the UK’s leading fee free mortgage broker. They’ll search 1000s of deals to find you the right mortgage.

Think carefully before securing other debts against your home. Your home may be repossessed if you do not keep up repayments on a mortgage or any other debt secured on it.

Useful links

Dive even deeper

What Credit Score Do You Need for a Mortgage?

It’s important to look at your credit score before applying for a mortgage because it can give you an idea of how a lender will view your application.

Should I Get a Fixed or Variable Mortgage?

The main difference between a fixed and variable mortgage is that your mortgage rate stays the same for a set period with a fixed-rate mortgage, while with a variable rate…

How Much House Can I Afford?

Get an estimate of how much house you can afford using our simple mortgage affordability calculator.