The Top 5 Mortgage Options for Buy-to-Let Investors

Choosing a buy-to-let mortgage can involve a lot of work. From the type of property you’re purchasing and how you intend to manage your investment to ensuring your longer-term plans all align with the mortgage products that are available to you.

Fortunately, there are several ways to finance a rental property. However, each option comes with different lending criteria, costs and considerations.

In this article, we explain everything you need to know about the top five mortgage options buy-to-let investors need to know. Let’s get started.

1. Five-Year Fixed-Rate Buy-to-Let Mortgages

A five-year fixed-rate buy-to-let mortgage keeps your interest rate the same for five years. This can help provide predictable monthly mortgage payments throughout the fixed period and can be a suitable mortgage product for investors who are prioritising certainty over their mortgage costs when managing rental income, maintenance expenses and other property-related costs.

For example, consider a £200,000 interest-only buy-to-let mortgage with a five-year fixed interest rate of 5%.

• Mortgage balance: £200,000
• Fixed interest rate: 5%
• Monthly interest payment: Approximately £833
• Fixed-rate period: Five years

The main benefit of a fixed term is that even when wider mortgage interest rates increase during those five years, your contractual monthly interest payment will remain the same, provided the mortgage balance and terms do not change.

However, it’s important to note that while your mortgage interest rate is fixed, other expenses such as maintenance, insurance and periods without tenants can still affect your rental income and overall profitability.

Should I Fix My Mortgage for 5 Years?

Fixing your buy-to-let mortgage for five years may be suitable if you intend to keep your rental property for the foreseeable future and prefer predictable mortgage payments.

The main advantage is knowing how much interest you will pay each month, allowing you to more easily budget and manage your property finances around your other everyday outgoings.

However, there are some important considerations:

• Falling interest rates: You will not automatically benefit if mortgage rates decrease during your fixed period
• Early repayment charges: Selling your property or remortgaging before your deal ends could result in additional charges
• Changing investment plans: A longer fixed period may be less suitable if you intend to sell, refinance or restructure your property portfolio within five years

For these reasons, some landlords may prefer a shorter 2-year fixed term over a 5-year period, particularly if you anticipate remortgaging, expanding your portfolio, or want to take advantage of any potential changing interest rates.

If you’re unsure whether a five-year fixed rate mortgage is the right choice for you, a mortgage broker can help you compare available deals, including interest rates, fees and early repayment charges. It’s important to understand all of your options to find a suitable mortgage that works for your circumstances.

2. Two-Year Fixed Rate Buy-to-Let Mortgages

A two-year fixed-rate buy-to-let mortgage keeps your interest rate the same for two years, providing predictable monthly payments while allowing you to review your mortgage options sooner than with a longer fixed-rate deal.

This option may appeal to landlords who are looking for greater flexibility over their longer-term borrowing arrangements, or who expect their property investment plans to change.

For example, in practice a landlord planning to sell or refinance their rental property within the next few years may prefer a shorter fixed-rate period to avoid being tied into a longer deal.

However, it is important to note that two-year fixed-rate mortgages are not necessarily cheaper than five-year deals. Interest rates and product fees vary between lenders, and choosing a shorter fixed period means you could face higher borrowing costs when your deal ends.

As such, it’s important to consider the overall cost of borrowing, including arrangement fees, product charges and rental income requirements. Lenders will also assess affordability, often requiring the property’s rental income to exceed the mortgage interest payments by a specified margin.

When is a Two-Year Fixed Buy-to-Let Mortgage the Best Option?

A two-year fixed buy-to-let mortgage may be suitable for landlords who want greater flexibility over their borrowing arrangements or expect their property plans to change in the near future. Specifically, If you’re expecting interest rates to fall or plan to remortgage in the near future, a two-year fixed mortgage term can help you keep costs lower while staying agile with your investment strategy.

Below we have provided a quick list of when a shorter-term fixed mortgage could be the best option:

• Planning to Remortgage or Sell: If you’re considering selling or refinancing your property within the next few years, a two-year fixed deal may help you avoid committing to a longer fixed-rate period. However, early repayment charges may still apply
• Reviewing Interest Rates Sooner: A shorter fixed period allows you to review available mortgage deals sooner. This could be beneficial if rates fall, although there is no guarantee that more competitive rates will be available
• Expanding Your Property Portfolio: If you’re planning to purchase additional rental properties or restructure your existing investments, a shorter fixed period may offer greater flexibility when reviewing your borrowing arrangements

Ultimately, a two-year fixed buy-to-let mortgage may appeal to landlords who prefer shorter commitments, but it’s important to consider the potential costs of refinancing and the risk of higher interest rates when your deal ends.

Overall, a two-year fixed buy-to-let mortgage is ideal for landlords who want short-term flexibility or are planning to adjust their property investments in the next few years.

3. Limited Company or SPV Buy-to-Let Mortgages

A limited company buy-to-let mortgage allows landlords to purchase or remortgage rental properties through a company rather than in their personal name, helping to divide personal and business finances.

Many lenders prefer the company to be established as a Special Purpose Vehicle (SPV), which is a limited company set up specifically for property-related activities, such as buying and letting residential properties.

An SPV buy-to-let mortgage works much like a standard mortgage, but the property must be owned by a company that is set up specifically for rental purposes. While an individual can run a buy-to-let business, the term SPV usually applies to companies because they must list their business activities on Companies House using SIC codes.

This ownership structure can offer certain tax advantages, particularly for landlords with multiple properties. However, it also comes with additional costs, responsibilities and lending requirements.

What Are the Benefits of an SPV Buy-to-Let Mortgage?

One potential advantage of owning rental property through a limited company is how mortgage interest and rental profits are treated for tax purposes.

Unlike individual landlords, who are generally subject to restrictions on mortgage interest tax relief for residential rental properties, limited companies can generally obtain Corporation Tax relief for qualifying mortgage interest costs.

For example, if a limited company receives £1,200 in monthly rental income and pays £700 in qualifying mortgage interest, those interest costs can generally be taken into account when calculating its overall taxable profits.

However, this does not mean the remaining £500 is automatically the company’s taxable profit. Other allowable expenses, income and relevant tax rules must also be considered.

There are several potential benefits to consider:

• Mortgage Interest Tax Relief: Qualifying mortgage interest costs can generally receive Corporation Tax relief, unlike the restrictions applying to individual residential landlords
• Portfolio Management: Holding multiple rental properties through a company can provide a structured approach to managing property finances and ownership
• Reinvesting Profits: Profits retained within the company may be available for future property purchases or other business expenses, subject to applicable taxes and financial commitments

What Are the Disadvantages of an SPV Buy-to-Let Mortgage?

Although limited company ownership can be beneficial in certain circumstances, it is not necessarily the most cost-effective option for every landlord.

Some important considerations include:

• Mortgage Costs: Limited company buy-to-let mortgages may have different interest rates, arrangement fees and deposit requirements compared with personal buy-to-let mortgages
• Company Administration: Running a limited company involves additional responsibilities, including maintaining company records, filing accounts and submitting Corporation Tax returns
• Personal Guarantees: Lenders commonly require directors to provide personal guarantees, meaning they could become personally liable for the company’s mortgage debt
• Tax on Withdrawn Profits: Taking money out of the company may create additional personal tax liabilities, depending on how the funds are withdrawn

If you already own a rental property personally, transferring it into a limited company can also have significant tax and legal implications, including potential Stamp Duty Land Tax and Capital Gains Tax liabilities.

For these reasons, it’s important to seek professional tax advice before deciding whether a limited company structure is suitable for your property investment plans.

Ultimately, a limited company or SPV buy-to-let mortgage can be a smart move for landlords aiming to grow their property portfolio while keeping their finances structured and tax-efficient.

4. HMO and Multi-Unit Buy-to-Let Mortgages

Houses in Multiple Occupation (HMOs) and multi-unit properties can offer opportunities to generate rental income from multiple tenants or self-contained units. However, financing these properties often requires specialist mortgage products, as lenders may apply different criteria compared with standard single-let buy-to-let properties.

A HMO mortgage can differ from a typical buy-to-let mortgage in the following ways:

• Lender Criteria: HMO mortgages will usually have stricter eligibility requirements. Many lenders expect landlords to have previous letting experience or own at least one standard buy-to-let property already.
• Property Valuation: Many lenders will assess HMOs differently, sometimes basing valuations on rental income potential rather than market value alone.
• Deposit Size: HMO mortgages are perceived to have a greater risk for lenders. To offset this, many HMO mortgage deals will require a larger deposit which can often be 25% or more.
• Interest Rates: The initial rates for HMO mortgages are generally higher than standard buy-to-let products.
• Licensing and Compliance: HMO properties must meet local council licensing rules and stricter safety regulations. Lenders will require this evidence to accept any mortgage deal.

It’s important to note that when exploring HMO buy-to-let mortgage options, lenders will typically assess whether the projected rental income meets their affordability and rental coverage requirements. The property must also comply with applicable HMO safety and licensing regulations.

If you’re unsure what’s required, read our latest article to discover how you can get a mortgage with an HMO licence.

5. Green or Energy-Efficient Buy-to-Let Mortgages

Green mortgages are designed for landlords purchasing or remortgaging energy-efficient rental properties. Some lenders offer preferential interest rates, cashback or other incentives for properties that meet certain Energy Performance Certificate (EPC) requirements.

Eligibility varies between lenders, with some green mortgage products available for properties rated EPC A, B or C.

What Are the Benefits of Green Buy-to-Let Mortgages?

Green buy-to-let mortgages may offer several advantages for landlords investing in energy-efficient properties:

• Mortgage Incentives: Some lenders offer preferential rates, cashback or other benefits for properties that meet their energy-efficiency requirements
• Lower Energy Costs: Energy-efficient properties may have lower heating and energy costs, potentially making them more attractive to tenants
• Future Energy Standards: Improving a property’s energy efficiency may help landlords prepare for upcoming changes to minimum energy-efficiency requirements

However, green buy-to-let mortgages are not necessarily cheaper than standard mortgage products. Landlords should compare interest rates, arrangement fees and other costs before choosing a deal.

What Should Landlords Consider?

A property’s EPC rating can affect its eligibility for certain green mortgage products, but landlords should also consider the cost of any energy-efficiency improvements.

In England and Wales, privately rented properties generally need an EPC rating of at least E, unless a valid exemption applies.

The government has confirmed plans to introduce higher minimum energy-efficiency standards for privately rented homes from 1 October 2030, subject to the necessary legislation. Landlords should consider how these changes could affect their properties and any improvements required.

When comparing green buy-to-let mortgages, it’s important to consider the overall cost of borrowing rather than focusing solely on the advertised interest rate or incentives.

At Boon Brokers, our dedicated mortgage experts can help you find the right green mortgage to match your property goals. With whole-of-market access, we compare the latest deals across lenders to ensure you secure a mortgage that truly fits your needs.

Key Considerations for Buy-to-Let Mortgages in the UK

Whatever your investment plans, when applying for a buy-to-let mortgage, there are several important factors landlords should keep in mind.

Here we have created a short checklist of the key considerations that can help make your mortgage application quicker and help you avoid surprises. Key factors to consider include:

• Loan-to-Value (LTV): Keeping a lower loan to value ratio usually means better interest rates and lower risk for lenders.
• Fees and Arrangement Costs: Look beyond the initial rate and make sure to compare the total costs, including arrangement fees and product charges.
• Interest Rate Type and Fixed: Understanding the differences between fixed and variable-rate mortgages can help you weigh up predictable repayments against the possibility of interest rate changes.
• Rental Cover and Stress Test: Lenders will typically expect your rental income to comfortably exceed your mortgage repayments.
• Property Type: Exact requirements from lenders can vary depending on whether it’s a single-let, HMO, multi-unit property, or part of a larger portfolio.
• Mortgage Structure (Personal vs Company): Borrowing through a limited company or SPV can affect tax efficiency and costs.
• Flexibility and Exit Costs: Check early repayment charges, break clauses, and how easy it will be to remortgage later.

Understanding and keeping each of these points in mind can help you plan your buy-to-let property investments more effectively. Working with a trusted mortgage broker for landlords can also help you save time.

Can a Mortgage Broker Help Buy-to-Let Investors?

Yes, a mortgage broker can help buy-to-let investors compare mortgage options, understand lenders’ requirements and find a suitable deal for their rental property.

Understanding the different types of mortgages available can also help you distinguish between standard residential products and specialist buy-to-let arrangements, which often have different lending criteria and affordability requirements.

Whether you’re purchasing your first rental property, remortgaging or expanding an existing portfolio, choosing the right mortgage involves considering interest rates, rental income requirements, fees and your longer-term investment plans.

At Boon Brokers, we provide fee-free, whole-of-market mortgage advice, with access to over 90 UK lenders. Our FCA-regulated mortgage experts can help you explore your options and guide you through the application process.

Boon Brokers can help you:

• Compare Mortgage Deals: Explore buy-to-let mortgage options from across the market, including specialist lenders
• Understand Lending Criteria: Assess rental income requirements, deposit sizes and property eligibility
• Explore Specialist Mortgages: Find suitable options for limited company, HMO and multi-unit properties
• Manage Your Application: Receive dedicated support from your initial enquiry through to mortgage completion
• Save on Broker Fees: Benefit from expert mortgage advice without paying a broker fee

We’ll help take care of your application from start to finish – handling all the paperwork, liaising directly with lenders, and guiding you through every stage of the process.

Contact Boon Brokers today and explore buy-to-let investments with an expert mortgage adviser who is ready to help you.