Interest-Only Mortgage Numbers Plummet for Owner Occupiers in 2025
The number of interest-only mortgages held by owner occupiers in the UK has fallen sharply, according to the latest data from UK Finance, the lenders' trade body. Figures recorded at the end of 2025 reveal a significant and continuing decline in this type of mortgage product, reflecting broader shifts in how British homeowners are choosing to finance their properties. Whether you are a current interest-only borrower, a prospective homebuyer, or a property professional, understanding these trends is essential for navigating today's mortgage landscape.
The Key Numbers: What the Data Shows
According to UK Finance data, there were 445,000 pure interest-only homeowner mortgages outstanding at the end of 2025. That represents a decline of 17.7% compared to the figures recorded in 2024, a substantial drop by any measure. In addition to pure interest-only deals, there were a further 156,000 partial interest-only homeowner mortgages outstanding at the same point in time. This figure was 10.3% lower than the equivalent number in 2024.
When you combine both categories, the total interest-only mortgage stock for owner occupiers has continued its long-running downward trajectory. The pace of that decline is accelerating, with the drop in pure interest-only deals being notably steeper than in previous years. For context, interest-only mortgages once represented a much larger slice of the UK residential mortgage market, making this trend all the more striking.
What Is an Interest-Only Mortgage?
For those unfamiliar with the product, an interest-only mortgage is one where the borrower pays only the interest on the loan each month, rather than also paying down the capital balance. This keeps monthly repayments lower in the short term, but means the full loan amount is still owed at the end of the mortgage term. Borrowers are expected to have a separate repayment vehicle — such as an investment, savings plan, or pension — in place to repay the capital when the term ends.
A partial interest-only mortgage, sometimes called a part-and-part mortgage, splits the loan so that some of it is on an interest-only basis and the rest is on a standard capital repayment basis. This gives borrowers slightly lower monthly payments than a full repayment mortgage while still chipping away at part of the debt over time.
Why Are Interest-Only Mortgage Numbers Declining?
The fall in interest-only mortgage numbers among owner occupiers is not a new phenomenon, but the rate at which numbers are dropping has intensified. Several factors are driving this trend.
Tighter Lending Criteria Since the Financial Crisis
In the years following the 2008 financial crisis, regulators and lenders significantly tightened the rules around interest-only lending. The Mortgage Market Review, introduced by the Financial Conduct Authority in 2014, made it much harder for borrowers to qualify for interest-only deals. Lenders now require robust evidence of a credible repayment strategy before approving this type of mortgage. As a result, new interest-only lending to owner occupiers has been limited for over a decade, and the existing stock has been steadily shrinking as older loans mature or are converted.
Borrowers Switching to Repayment Mortgages
Many existing interest-only borrowers have proactively switched to capital repayment mortgages, either out of concern about their ability to repay the outstanding balance at the end of the term or because they have been encouraged to do so by their lender. UK Finance and individual mortgage providers have long run outreach programmes aimed at interest-only borrowers approaching the end of their terms, urging them to review their arrangements and take action where needed.
Natural Maturity of the Mortgage Stock
A significant proportion of the remaining interest-only mortgages were taken out during the late 1990s and 2000s, when the product was far more widely available and popular. As these older loans reach their natural end dates, they are either repaid in full or converted into repayment products. With fewer new interest-only mortgages being written for owner occupiers to replace them, the total stock continues to shrink.
Changing Consumer Attitudes
There has also been a cultural shift in how homeowners think about their mortgages. The idea of sitting with a large outstanding debt and hoping that an investment vehicle will cover it at the end of the term is a less comfortable proposition for many borrowers in today's environment of economic uncertainty. Most new borrowers now default to repayment mortgages as the safer and more straightforward option.
What Does This Mean for Existing Interest-Only Borrowers?
If you currently hold an interest-only mortgage as an owner occupier, the declining numbers are a reminder to review your repayment strategy sooner rather than later. Key questions to ask yourself include the following.
- Do you have a credible and sufficient repayment vehicle in place to cover the full outstanding balance when your mortgage term ends?
- Has your investment or savings plan performed as expected, or has there been a shortfall in growth?
- How many years remain on your mortgage term, and is there still time to address any gap in your repayment plan?
- Have you spoken to your lender recently about your options, including switching to a full or partial repayment mortgage?
It is worth seeking independent mortgage advice if you are uncertain about your position. A qualified mortgage adviser can help you assess your options and take the appropriate steps to protect your home and your finances.
Implications for the Broader UK Mortgage Market
The ongoing decline in owner-occupier interest-only mortgages is broadly seen as a positive development for the stability of the UK housing market. Reducing the number of borrowers who face a large capital repayment at the end of a fixed term lowers the risk of mortgage shortfalls and potential repossessions. It also reflects the success of regulatory reforms introduced following the financial crisis.
For the mortgage industry, the shrinking stock of interest-only deals means lenders and brokers are handling fewer complex conversations around end-of-term repayment strategies. However, the proportion of borrowers who may still face a shortfall — particularly those who took out interest-only deals backed by underperforming endowment policies decades ago — continues to require careful management and proactive communication from lenders.
Looking Ahead: Will Interest-Only Mortgages Continue to Fall?
Given the strict lending criteria currently in place and the relatively small number of new interest-only mortgages being originated for owner occupiers, the total stock is almost certain to continue declining in the years ahead. Unless there is a significant regulatory or market shift that makes interest-only products more accessible to residential borrowers, the downward trend appears set to continue well into the late 2020s.
For buy-to-let investors, the picture is somewhat different, as interest-only mortgages remain far more common in that sector. However, for owner occupiers, the era of widespread interest-only borrowing appears to be firmly drawing to a close.
The data from UK Finance underlines the importance of staying informed about your mortgage and planning ahead. Whether you are a homeowner, a first-time buyer weighing up your options, or a property professional advising clients, keeping a close eye on mortgage market trends will help you make better, more confident decisions.