Mortgage overpayments and underpayments

Making overpayments and lump-sum repayments towards your mortgage can help you pay it off sooner and save you money overall. 

You might also be able to make underpayments – your mortgage offer will tell you if it’s possible with your mortgage. Please see ‘About underpayments’ on this page for more information about how it works and how to apply.

If you’re looking to pay off your mortgage, find out how to pay it off in full.

Who’s this guide for?

It’s for you if your mortgage account number has 10 numbers. If it has six numbers, or if you have questions about overpayments, lump-sum repayments or underpayments, please call us on 0333 202 7580¹. We’re here Monday to Friday, from 7am to 8pm (except bank holidays) and from 7am to 5pm at weekends. If you’d rather chat to us online, log in to Online Banking and start a web chat.

What you need to know first 

Your term won’t change

Making overpayments, lump-sum repayments or underpayments won’t change your mortgage term. We’ll still expect you to pay off your mortgage over the term you originally agreed. Please call us if you’d like to change your mortgage term.

We won’t give any refunds 

We won’t refund any overpayments or lump-sum repayments, so you might want to think about repaying any borrowing with higher interest first, like an overdraft. If you’d rather be able to access your money in an emergency, take a look at our range of savings accounts instead.

You still need to make your contractual monthly payment

You always need to make your contractual monthly payment (CMP) unless we’ve agreed otherwise. This is in your mortgage offer as your ‘regular monthly payment’, or in your most recent payment notification if your CMP has changed since you got your offer.

When you have more than one mortgage on a property, for example if you’ve taken out additional borrowing, each one will have its own mortgage offer, account and CMP. If you pay by Direct Debit, the amount we collect each month is the total of all your CMPs.

If your mortgage is a combination of repayment and interest-only, both parts are on one account so you’ll only have one CMP.

If you’ve missed payments or owe charges

If you’ve missed any payments or owe charges on your mortgage, please call us on 0800 022 4022¹ before making overpayments or lump-sum repayments. We’re here Monday to Friday, from 8:30am to 5:30pm, and from 9am to 1pm on Saturdays. 

Lump-sum repayments to reduce your total mortgage costs

When you make an additional mortgage payment that’s at least three times your CMP, we call this a ‘lump-sum repayment’ (it may also be called a ‘part redemption’). Making lump sum repayments reduces the amount of interest you are charged – which means it’ll cost you less overall.

Here’s how it works:

• We apply the lump-sum repayment to the balance you owe us, reducing it by that amount
• As you owe less, we charge you less interest
• Your CMP will normally reduce, as you’ll be repaying a reduced balance over the remainder of your original term.

If you’re thinking about making a lump-sum repayment, please see the ‘Flexible features’ section of your mortgage offer for more details. You might need to pay an early repayment charge (ERC) – please see ‘Early repayment charge (ERC)’ below for details.

Your monthly payment will usually change

When you make a lump-sum repayment, we’ll send you a revised payment notice confirming your new CMP. If you pay by Direct Debit, you don’t need to do anything – we’ll update your payments for you. If you pay any other way, you’ll need to change your payments to the new amount.

Keep your payment the same by making overpayments

You can also choose to keep paying the same each month as you did before your CMP reduced. This means you’ll be making overpayments, which can further reduce your mortgage costs and help you pay off your mortgage sooner. You can do this by increasing your Direct Debit or standing order, or by making an additional payment each month.

If your mortgage is a combination of repayment and interest-only

If your mortgage is combination of repayment and interest-only, we’ll apply the lump-sum repayment to the interest-only part. Please call us if you’d like to change this to the repayment part. 

If you’re switching your interest rate 

If you’re switching your interest rate with us and want to make a lump-sum repayment without paying an ERC, you can either:

• Make a lump-sum repayment equal to up to 90% of your mortgage balance between 90 and 31 days of your current rate ending
• Make a lump-sum repayment of any amount within 30 days of your current rate ending.

For example, your mortgage balance is £100,000 and the rate you have now ends on 30 November 2025.

Here’s what you could pay before needing to pay an ERC:

• Up to £89,999.99 between 2 September 2025 and 31 October 2025.
• Up to £99,999 between 1 November 2025 and 30 November 2025.

Overpayments to pay off your mortgage early 

When you make an additional mortgage payment that’s less than three times your CMP, we call it an overpayment. Making overpayments can help you pay off your mortgage sooner, when the amount you owe equals the amount of your overpayment balance – which means it’ll cost you less overall.

Here’s how it works:

• We put any overpayments in an overpayment account linked to your mortgage account
• We reduce the balance you’re charged interest on each month by the amount you’ve overpaid 
• Your CMP and mortgage term don’t change
• You can use the balance of your overpayment account to pay off your mortgage sooner than you would otherwise 
• You might also be able to use the balance of your overpayment account to make underpayments, if your mortgage allows this.

You can make as many overpayments as you like, and there’s no minimum to the amount of each one. 

You can also choose to apply your overpayment balance as a lump-sum repayment, which will usually reduce your CMP, as explained above.

If your mortgage is a combination of repayment and interest-only

If your mortgage is a combination of repayment and interest-only, we’ll apply any overpayments to the repayment part. Please call us if you’d like to change this to the interest-only part. 

Checking your overpayment account balance

Your mortgage balance in our app and in Online Banking includes the balance on your overpayment account. This lets you see your total capital balance (without any interest, fees or charges).

Your annual mortgage statement shows your overpayment account balance on the date we issued the statement. If you’ve since made overpayments or underpayments, your overpayment account balance might have changed. To see it in Online Banking:

1. Select ‘Borrow’ on the home page
2. Select ‘Manage my mortgage’
3. Choose the mortgage account you want to see your overpayment account balance for
4. Go to ‘Mortgage management’
5. Select ‘Set up an underpayment’. You’ll see your ‘Pre-payment balance’ which is the same as your overpayment account balance.

Or you can call us..

Early repayment charge (ERC)

To see if and when an ERC will apply to any lump-sum repayment you make, see the ‘Early repayment’ section of your mortgage offer. 

Unless your mortgage offer states otherwise, your ERC is a fixed percentage amount. Your mortgage offer will tell you what percentage your ERC is.

You can see how much you can overpay without having to pay an ERC in the 'Flexible features' section of your mortgage offer. 

How to make lump-sum repayments and overpayments

From a bank account with us

Here are the different ways you can make these payments:

In our App

1. On the home page, select the mortgage account you want to make the payment to 
2. Choose how you want to pay (transfer or debit card) and follow the on-screen instructions.

In Online Banking

1. On the home page, select ‘Borrow’, then ‘Manage my mortgage’
2. Choose the mortgage account you want to make the payment to, then ‘Mortgage management’ 
3. Select the type of payment you want to make (single overpayment, regular overpayments, or debit card payment), and follow the on-screen instructions.

In both our app and Online Banking, you’ll only see the option to make overpayments. But if you make a payment that’s three times your CMP or more, we’ll treat it as a lump-sum repayment.

From an account with another bank

Please use these paying-in details:

• Sort code 23-88, plus the first two numbers of your 10-digit mortgage account number
• Account number – this is the last 8 digits of your mortgage account number.

Please check with your bank for any limits they apply to the amount you can pay.   

About underpayments

An underpayment is when you pay less than your CMP. If you want to use your overpayment balance to make underpayments, you can if:

• Your mortgage offer allows them
• You have an overpayment account balance big enough to top up any underpayments so they equal your CMP
• We’ve agreed you can. 

If you’re thinking about making underpayments because you’re worried about money, see how we can help. Or call us on 0333 202 7504¹ – we’re here Monday to Thursday from 8am to 8pm, Friday 8am to 6pm and from 9am to 1pm on Saturdays. 

How to apply to make underpayments 

To apply to make underpayments in Online Banking:

1. On the home page, select ‘Borrow’ then ‘Manage my mortgage’
2. Choose the mortgage account you want to set up underpayments for, then ‘Mortgage management’ 
3. Select ‘Set up an underpayment’ and follow the on-screen instructions. You can see your overpayments balance under ‘Pre-payment balance’.

We’ll then give you a call to talk it through.

Please call us on 0333 202 7504¹ if you don’t see the ‘Set up an underpayment’ option. 

Where to find your mortgage offer

In our app

1. Select ‘More’ at the bottom of the screen
2. In ‘Statements and documents’, choose ‘Documents’.

In Online Banking

1. Select ‘Manage accounts’ on the home page
2. In ‘Statements and documents’, select the mortgage account you want to see the offer for
3. You’ll find it under ‘Documents’.

Not yet registered?

If you haven’t already, you can download our app from your app store or register for Online Banking. 

If you’d rather talk to us, just give us a call and we can go through how overpayments, lump-sum repayments and underpayments work. You can also ask us to send you a copy of your mortgage offer, if you need one.

Watch our video guides

Our video guides show you how to pay more towards your mortgage using our app and Online Banking.