Offset Mortgages: The Ultimate Guide

Offset mortgage illustration with a house and savings pot on balanced scales

Table of Contents

Offset Mortgages Explained: Advantages, Disadvantages & Tips

What is an Offset Mortgage?

An offset mortgage is a type of mortgage where a borrower’s savings account is linked to their mortgage account, with the savings balance used to reduce the mortgage balance on which interest is calculated. This unique feature allows borrowers to save money on interest payments and potentially pay off their mortgage faster, without necessarily having to make higher monthly payments.

They work by ‘offsetting’ the balance of a borrower’s savings account against their outstanding mortgage balance. Instead of earning interest on the savings, the interest that would have been earned is instead used to reduce the amount of interest charged on the mortgage. This means that borrowers effectively pay interest on a smaller mortgage balance, which can lead to significant interest savings over the life of the mortgage.

How does it differ from a regular mortgage?

With a traditional mortgage, borrowers make monthly payments to cover the interest and gradually reduce the principal amount borrowed. The interest is calculated based on the full outstanding mortgage balance. In contrast, with an offset mortgage, the interest is calculated on the mortgage balance minus the balance of the linked savings account.

A key difference is that traditional mortgages do not take a borrower’s savings into account, while offset mortgages directly link the savings account to the mortgage, allowing borrowers to benefit from their savings without needing to make higher monthly payments or overpayments.

How Does an Offset Mortgage affect interest or payments?

When a borrower has an offset mortgage, their savings account is linked to their mortgage account. The savings balance is then used to ‘offset’ the outstanding mortgage balance, reducing the amount of interest calculated and charged. For example, if a borrower has a mortgage balance of £200,000 and a savings balance of £20,000, they would only pay interest on £180,000 (£200,000 – £20,000).

The borrower’s monthly mortgage payments may still be based on the full mortgage balance, but a portion of each payment will cover the interest on the reduced balance, enabling them to pay off the principal more quickly. It’s important to note that the savings are not used to directly pay off the mortgage; they simply reduce the balance on which interest is calculated. The savings remain accessible, giving borrowers flexibility in managing their finances.

Examples of how to save money using an offset mortgage

Here are some examples of how an offset mortgage can help borrowers save money:

  1. Interest savings: If a borrower has a mortgage balance of £200,000 with a 4% interest rate and a savings balance of £20,000, they would pay interest on £180,000 instead of £200,000. Over the life of a 25-year mortgage, this could save them thousands of pounds in interest payments.
  2. Faster mortgage repayment: As borrowers effectively pay interest on a smaller mortgage balance, they can pay off their mortgage faster without making higher monthly payments. This can shorten the mortgage term and save even more on interest payments.
  3. Flexibility: These mortgages provide financial flexibility, as borrowers can access their savings if needed. They can also make overpayments without penalty, allowing them to pay off their mortgage even faster if their financial situation permits.

It’s important to note, however, that offset mortgages may not be the best option for everyone. Borrowers should carefully evaluate their financial situation, including their savings balance and ability to maintain regular deposits into the linked savings account, to determine if an offset mortgage is the right choice for them. Additionally, borrowers should be aware that offset mortgages may have higher interest rates and fees compared to traditional mortgages, which could eat into some of the potential interest savings.

Despite these considerations, offset mortgages can be a valuable financial tool for many borrowers, particularly those with substantial savings or the ability to regularly contribute to their savings account. By carefully weighing the advantages and disadvantages of offset mortgages, borrowers can make the most of their mortgage and savings to achieve their homeownership and financial goals.

A great deal of care must be taken to ensure that this strategy will fit your needs long term. It can be very easy to assume that the savings will be there, but if the balance isn’t maintained, or savings increased over time then the mortgage itself will just be a more expensive option than it could have been. At AALTO Mortgages we have been advising clients about complex mortgage needs for over a decade. We know the right questions to ask, the appetite of the lenders and can provide you a personalised quote and advice through the whole process to ensure you always know exactly what the best option is for you.

Advantages & Disadvantages

Offset mortgages can offer significant benefits to some borrowers, but they also come with potential drawbacks. Understanding both the advantages and disadvantages is crucial for determining whether an offset mortgage is the right choice for your financial needs and goals.


Saving on interest payments and paying off your mortgage faster – As mentioned earlier, an offset mortgage allows you to save on interest payments by reducing the balance on which interest is calculated. This not only saves you money over the long term but also enables you to pay off your mortgage faster without necessarily increasing your monthly payments.

Other potential benefits, such as tax advantages and flexibility – Offset mortgages may offer tax advantages ,depending on your personal circumstances, as the interest saved may not be subject to income tax. Additionally, offset mortgages provide increased flexibility in managing your finances, as you can access your savings without penalty and make additional payments to further reduce your mortgage balance and interest charges.


Fees and charges associated with offset mortgages – Offset mortgages may come with higher fees and charges compared to traditional mortgages. These fees may include arrangement fees, valuation fees, and annual account fees. It’s important to carefully review and compare the fees associated with offset mortgages to ensure that the potential interest savings outweigh the costs.

What to consider before choosing an Offset Mortgage

Before choosing an offset mortgage, consider the following factors:

  • Your current savings balance and ability to maintain regular deposits into the linked savings account. There is a certain threshold where this becomes the best option, but very much depends on your circumstances.
  • The interest rates and fees associated with the offset mortgage compared to a traditional mortgage. Typically higher, so ensure you will utilise the feature fully.
  • Your financial goals, including whether you aim to pay off your mortgage faster or prioritize flexibility in managing your finances.
  • Any potential tax advantages or implications associated with offset mortgages in your jurisdiction. We recommend you speak with your tax advisor before committing.

Some common misconceptions include:

  • Offset mortgages are only suitable for high-income earners: While offset mortgages can be more beneficial for those with higher incomes and substantial savings, they can also offer advantages to borrowers with smaller savings balances.
  • Offset mortgages are always more expensive than traditional mortgages: While some offset mortgages may have higher fees, the potential interest savings can outweigh these costs for many borrowers.
  • Offset mortgages are only available for primary residences: Offset mortgages can be used to finance second properties and investment properties, subject to the lender’s eligibility requirements.

When choosing, consider the following factors:

  • Interest rate: Compare the interest rates of various offset mortgages to find the most competitive deal.
  • Fees: Examine any additional fees associated with the offset mortgage, such as account maintenance fees or application fees, to ensure that the mortgage remains cost-effective.
  • Flexibility: Look for features that provide flexibility, such as the option for additional repayments, redraw facilities, or the ability to split your mortgage between fixed and variable rates.
  • Linked account: Ensure that the linked savings account offers competitive interest rates and has no hidden fees.

Speak to us today on 0207 183 1101 and we will be happy to explain the process and criteria in more detail. AALTO Mortgages has over a decade of experience in dealing with offset mortgages, and we can provide you our industry leading knowledge and experience.

Additional information

Strategies for paying off your mortgage with an offset mortgage

Here are some strategies for using an offset mortgage to pay off your mortgage faster:

  • Make regular deposits into your linked savings account to maximize the offset effect and reduce interest payments.
  • Consider making additional mortgage repayments to further reduce the principal balance and shorten the mortgage term.
  • Adjust your repayment frequency from monthly to fortnightly or weekly, resulting in more frequent repayments and a faster reduction of your mortgage balance.

Can you use an offset mortgage to buy a second property?

Yes, either as an investment or a vacation home. The process is similar to applying for an offset mortgage for your primary residence. You will need to provide financial documentation, such as proof of income and bank statements, and meet the lender’s eligibility requirements. Keep in mind that lenders may have stricter criteria for financing second properties, including higher deposit requirements and more stringent affordability assessments.

When using an offset mortgage to buy a second property, consider the following factors:

  • Affordability: Ensure that you can comfortably manage the repayments on both your primary residence mortgage and the second property mortgage.
  • Deposit: Be prepared for a larger deposit requirement, as lenders often impose higher deposit requirements for second properties.
  • Rental income: If you plan to rent out the second property, consider potential rental income as part of your affordability assessment. However, be cautious not to rely solely on rental income to cover the mortgage repayments, as vacancies and rental fluctuations can impact your cash flow.
  • Tax implications: Owning a second property may have tax implications, such as capital gains tax or additional property taxes. Consult a tax professional to understand your obligations.
  • Insurance: Ensure that you have appropriate insurance coverage for your second property, including landlord insurance if you plan to rent it out.

Can you use an Offset mortgage with interest only?

Yes, very much so. Interest only options will be determined by the property itself. You can find more information about interest only criteria here. The two options are mutually exclusive and don’t conflict in terms of criteria. If you would qualify for interest only, then its choice you can make yourself. We would strongly recommend discussing such a strategy with a mortgage broker such as ourselves before making this commitment as there is significantly more risk with this approach.

Best offset mortgage deals: How to find them

To find the best offset mortgage deals, you need to do thorough research and compare different mortgage providers. Start by checking comparison websites, which can give you an overview of the available options and their respective interest rates. Next, visit the websites of individual banks and building societies to find more information about their specific offset mortgage offerings.

Consider consulting with a mortgage broker like AALTO Mortgages. Being whole of market we have every offset option available to us, and as we can provide personalized advice and have access to deals not available to the general public. We can also help you navigate the mortgage application process and find the best terms and rates for your specific financial situation.

Offset mortgage tips for first-time buyers

First-time buyers should be aware of several factors when considering an offset mortgage. Begin by assessing your finances, ensuring that you have a steady income and a good credit score. This will improve your chances of being approved for a mortgage and receiving favourable interest rates.

Next, set a realistic budget for your property search, taking into account the amount you can borrow, your deposit, and any additional costs such as stamp duty or legal fees. When evaluating offset mortgages, consider the amount of savings you have and how much you can continue to save each month. This will help you determine if an offset mortgage is the best option for you.

Mortgage Calculators

There are a number of calculators available that will demonstrate the long term savings and reduced monthly payments based on lump sum and regular savings. Running through some scenarios on these calculators can reveal just how much can be saved in the long term by being efficient with your savings. You can find Money Saving Experts excellent calculator here.

How interest rates affect offset mortgages

Interest rates play a significant role in determining the cost of an offset mortgage. A lower interest rate typically results in lower monthly repayments and less overall interest paid throughout the mortgage term. In an offset mortgage, the interest rate affects the amount of interest saved by offsetting the mortgage balance with savings in the linked account. A higher interest rate may result in more significant interest savings when using an offset mortgage, while a lower interest rate may yield smaller savings.

Picture of Author: Stuart Phillips

Author: Stuart Phillips

Fully CeMap qualified, Directly Authorised by the FCA and with over a decade of experience, Stuart has a wealth of experience in both specialist BTL and residential mortgages.

Need help with Offset Mortgages?

Here at AALTO Mortgages we have extensive experience with Offset Mortgages. Click below for contact options , or call now on 020 7183 1101 to speak with an experienced broker.
Get in touch

Contact Us

020 7183 1101

Services we offer

Related Articles

A british soldier standing in front of their new house denoting the theme of mortgages for armed services

A Comprehensive Guide to Mortgages for UK Military Personnel

Elderly couple signing documents at their dining table

Navigating the Intricacies of Retirement Interest-Only Mortgages: A Comprehensive Guide

An older couple in a modern setting signing a document on a tablet.

Navigating the Mortgage Landscape for Individuals Over 50: An In-Depth Guide

Rugby player signing a contract with a ball on the table

Mortgage Challenges & Solutions for Professional Athletes in the UK

Sign Up to the Newsletter

Get a weekly newsletter  with the latest rates, industry news and featured posts