The vast majority of buy-to-let mortgages in the UK are taken on an interest-only basis, but that does not mean it is the only option — or even the best one for every landlord. Repayment buy-to-let mortgages, where your monthly payments cover both interest and a portion of the capital, offer a fundamentally different approach to property investment. In this guide, we explore whether a repayment buy-to-let mortgage could be the right choice for you.
How do repayment buy-to-let mortgages work?
With a repayment mortgage, each monthly payment consists of two components: the interest charged on the outstanding loan and a portion of the capital (the original amount borrowed). In the early years, most of your payment goes towards interest, but as the loan balance reduces, an increasing proportion goes towards repaying the capital.
By the end of the mortgage term (typically 25 to 30 years), you will have repaid the entire loan and own the property outright with no mortgage debt.
This contrasts with an interest-only buy-to-let mortgage, where you pay only the interest each month. The loan balance stays the same throughout the term, and you need a separate plan to repay the capital at the end — usually by selling the property.
The mechanics of repayment mortgages mean that your equity in the property grows automatically every month, regardless of what happens to property values. After ten years of a 25-year repayment mortgage, you will typically have repaid around 30% of the original loan, and after twenty years, around 70%. This progressive equity build-up provides a valuable cushion against market fluctuations and strengthens your overall financial position as a landlord.
To see how the numbers compare for your situation, use our repayment calculator to model different scenarios.
Why do most landlords choose interest-only?
Before examining the case for repayment, it is worth understanding why interest-only dominates the buy-to-let market:
- Lower monthly payments — by only paying the interest, your monthly outgoings are significantly lower, improving your cash flow
- Higher rental yield — lower costs mean a greater proportion of rental income remains as profit
- Tax efficiency (historically) — before the changes to mortgage interest relief, the full interest payment was deductible from rental income. While this is no longer the case, the lower payment still keeps cash flow healthier
- Flexibility — many landlords prefer to keep their capital working across multiple properties rather than paying down debt on a single one
- Capital appreciation — if property values rise, the landlord benefits from the full increase regardless of whether they are repaying the capital
These are valid reasons, and for many investment strategies, interest-only remains the right choice. However, repayment mortgages have their own significant advantages.
The case for repayment buy-to-let
Building equity — the most obvious benefit is that you are steadily reducing your debt and building equity in the property. Over a 25-year term, you will own the property outright, creating a valuable unencumbered asset.
Guaranteed debt reduction — unlike relying on property price appreciation to build equity (which is not guaranteed), a repayment mortgage mechanically reduces your debt every month.
Lower total interest cost — over the life of the mortgage, you pay significantly less interest on a repayment basis because the outstanding balance reduces over time. On a £150,000 mortgage at 5% over 25 years, you would pay approximately £112,000 in total interest on repayment, compared to £187,500 on interest-only.
Retirement planning — if you plan to hold rental properties into retirement, having them mortgage-free provides a reliable income stream without the burden of mortgage payments. This is particularly attractive if you want rental income to supplement your pension.
Peace of mind — some landlords simply prefer the certainty of knowing their debt is being paid down. Not having to worry about a large capital repayment at the end of the term removes a significant source of financial stress.
Improved affordability for future lending — as your LTV improves on each property, you may qualify for better rates on remortgages or new purchases, and your overall portfolio leverage reduces.
The drawbacks of repayment
Higher monthly payments — the most significant drawback. On a £150,000 mortgage at 5% over 25 years, repayment costs approximately £877 per month compared to £625 on interest-only — a difference of £252 per month.
Reduced cash flow — the higher payments mean less monthly cash flow from the property, which could be the difference between a profitable investment and a marginal one, particularly in lower-yield areas.
Opportunity cost — the additional money going towards capital repayment could potentially be deployed elsewhere for a higher return — such as using it as a deposit on another property.
Less flexibility — if your financial circumstances change or the property market shifts, having lower monthly obligations (as with interest-only) gives you more breathing room.
Tax implications — under current rules, you receive a 20% tax credit on the interest element of your mortgage payments. With a repayment mortgage, the interest element decreases over time, so the tax credit also reduces. The capital repayment element has never been tax-deductible.
When does repayment make more sense?
There are several scenarios where a repayment buy-to-let mortgage may be the better choice:
Long-term hold strategy — if you plan to keep the property for the full mortgage term and want to own it outright, repayment is the logical choice. This is particularly true for properties in areas with strong rental demand that you view as lifelong income assets.
Approaching retirement — if you are in your 40s or 50s and want your properties to be mortgage-free by retirement, a repayment mortgage ensures this happens. Lenders may also prefer repayment if the mortgage term extends beyond your expected retirement age. Use our affordability calculator to understand how this affects your borrowing capacity.
Single property investors — if you have one or two buy-to-let properties and no plans to expand your portfolio, the argument for keeping debt high (to leverage into more properties) is less relevant. Paying down the mortgage makes more sense.
Risk-averse investors — if the thought of owing hundreds of thousands of pounds at the end of a 25-year term concerns you, repayment provides the certainty of debt reduction.
Strong rental yields — in areas where rental income comfortably covers repayment mortgage costs with room to spare, there is less reason to opt for interest-only just to preserve cash flow.
Combining repayment and interest-only
A strategy used by some experienced landlords is to use interest-only mortgages on some properties and repayment on others. This balances the cash flow benefits of interest-only with the equity-building advantages of repayment.
For example, you might use interest-only on properties in high-growth areas where you expect capital appreciation to build equity, while using repayment on properties in stable, high-yield areas that you plan to hold long term.
Some lenders also offer part-and-part mortgages, where a portion of the loan is on interest-only and the remainder is on repayment. This provides a middle ground, though availability for buy-to-let is more limited than for residential mortgages.
Use our interest-only vs repayment calculator to compare the costs and see how different splits affect your monthly payments.
Lender criteria for repayment buy-to-let
The good news is that lenders generally view repayment buy-to-let applications favourably, as the loan is being repaid over time rather than relying on a future repayment strategy.
The affordability assessment still involves the rental income meeting the ICR requirements, but some lenders apply slightly more relaxed criteria for repayment mortgages. The reasoning is that the reducing loan balance lowers the lender’s risk over time.
Other standard criteria apply:
- Minimum deposit — typically 25%, though some lenders offer 20% LTV for repayment
- Minimum income — usually £25,000 personal income
- Credit history — assessed in the same way as interest-only applications
- Property type — standard houses and flats are accepted by most lenders; HMOs and multi-units have more limited options
If you have any credit issues, our adverse credit specialists can help identify lenders who will consider your application. For a full overview of buy-to-let eligibility, visit our buy-to-let service page.
Making the right decision
The choice between repayment and interest-only ultimately depends on your personal financial goals, investment strategy, and risk tolerance. There is no universally correct answer — both approaches have genuine merits.
Consider these questions:
- What is your investment timeline? Short-term flips and medium-term holds may suit interest-only, while long-term holds suit repayment.
- Do you want to build a larger portfolio? Interest-only keeps more capital available for deposits on new properties.
- How important is cash flow? If maximising monthly income is your priority, interest-only is better.
- What is your plan for repaying the loan? If your only plan is to sell the property, consider whether you are comfortable with that reliance on future property values.
- How risk-averse are you? If market volatility worries you, repayment provides a guaranteed path to owning the property outright.
Our advisers at Option Finance can model both options for your specific circumstances, helping you make an informed decision. For broader guidance on the buy-to-let market, our ultimate UK buy-to-let mortgage guide covers everything you need to know.
Switching from interest-only to repayment
If you currently have an interest-only buy-to-let mortgage and are considering switching to repayment, there are a few practical points to be aware of.
Product transfer — if your current lender offers repayment buy-to-let products, you may be able to switch through a product transfer when your existing deal expires. This is often the simplest route, as it avoids a full remortgage application with a new lender.
Remortgaging — alternatively, you can remortgage to a new lender on a repayment basis. This gives you access to the whole market and may deliver a better interest rate, but involves a full application, valuation, and legal process. Check our latest remortgage deals to see current market rates.
Remaining term considerations — if you switch to repayment later in the mortgage term, the remaining years are shorter, which means the monthly payments will be higher than if you had been on repayment from the start. For example, switching to repayment with 15 years remaining results in higher monthly payments than starting on a 25-year repayment term, because the capital must be repaid over a shorter period.
Affordability impact — the higher monthly payments on a repayment basis need to be covered by the rental income (or supported by your personal income, depending on the lender). If the property’s rental yield is tight on an interest-only basis, the increased costs of repayment may push the ICR below the lender’s threshold.
Partial switch — some lenders allow a part-and-part arrangement where you switch a portion of the loan to repayment while keeping the rest on interest-only. This can be a good middle ground if a full switch to repayment would stretch the affordability too far.
Our ultimate UK buy-to-let mortgage guide provides comprehensive coverage of all these options, and our mortgage calculator can help you model the payment differences.
Repayment buy-to-let and later life lending
One area where repayment buy-to-let is particularly relevant is for older borrowers. If you are approaching or past retirement age, many lenders prefer or even require a repayment mortgage because this aligns with their risk assessment criteria. For more on planning ahead, see our ultimate UK remortgage guide.
- The mortgage term extends into or beyond retirement, when income typically reduces
- There is less time for property appreciation to build equity on an interest-only basis
- Lenders want assurance that the loan will be fully repaid within a reasonable period
Some specialist later life lenders offer buy-to-let products specifically designed for older borrowers, with terms that account for pension income and a longer-term investment horizon. If you are in this situation, a specialist broker can help identify the most appropriate options.
Speak to an expert
Whether you are leaning towards repayment, interest-only, or a combination of both, getting professional advice ensures you choose the structure that best supports your investment goals. At Option Finance, we take the time to understand your long-term plans and recommend the most appropriate mortgage structure. Apply now to discuss your buy-to-let mortgage options with one of our experienced advisers.
About the Author
Benjamin KistellMortgage and Protection Specialist
CeMAP, CeRER, DipFA Qualified Mortgage Adviser
Benjamin manages mortgage applications from start to finish, ensuring every piece of documentation is in order and deadlines are met. His meticulous attention to detail and proactive communication style mean clients are always kept informed throughout the process. He handles the day-to-day coordination between clients, lenders, and solicitors to keep everything on track.
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