Limited company buy to let mortgage basic rate taxpayer interest only products have become increasingly popular among UK landlords seeking tax-efficient ways to finance investment property. This type of buy-to-let lending allows investors to purchase or remortgage rental properties through a limited company structure, while paying only the interest on the loan each month. For basic rate taxpayers, this setup can offer significant benefits, especially when navigating the complexities of Section 24 tax relief restrictions. With rising interest rates and tighter affordability rules in 2025, many landlords are turning to limited company buy-to-let mortgages as a way to optimise returns and manage costs. These landlord mortgage products are particularly attractive for portfolio landlords and those planning long-term property investment strategies.
Quick Facts
– Interest rates: 5.25% to 6.75% (2025 average)
– Minimum deposit: 25% (some lenders require more)
– Rental coverage: 125% to 145% of mortgage interest at a stress-tested rate
– Maximum loan-to-value (LTV): 75%
– Arrangement fees: Typically 1% to 2% of the loan amount
– Application timeline: 4 to 8 weeks depending on lender and complexity
Limited company buy-to-let mortgages in 2025 typically require a 25% deposit and are assessed based on projected rental income rather than personal income. Interest-only options help keep monthly payments lower, but affordability is still stress-tested at higher interest rates. These mortgages are available from specialist lenders and require careful planning to meet lender criteria and tax regulations.
How This Mortgage Works
A limited company buy to let mortgage basic rate taxpayer interest only works by allowing a landlord to borrow through a special purpose vehicle (SPV) limited company, instead of in their personal name. The mortgage is structured as interest-only, meaning the borrower pays only the interest each month, with the capital repaid at the end of the term or through a remortgage or property sale.
These products are commonly offered with fixed, variable, or tracker interest rates. Fixed-rate deals (typically 2 to 5 years) are popular for budgeting purposes, while tracker and variable rates may offer lower initial costs but come with more risk if rates rise.
This type of mortgage suits landlords looking to grow a portfolio, retain profits within a company, or benefit from more favourable tax treatment. It’s particularly efficient for basic rate taxpayers who want to avoid the personal tax implications of Section 24, which limits mortgage interest relief for individual landlords.
In 2025, lenders remain cautious but open to limited company applications, especially where the company is set up as an SPV with a clear SIC code related to property letting. These mortgages differ from residential loans in that affordability is based on rental income, not personal salary, and the underwriting process is more commercial in nature.
Eligibility and Criteria
To qualify for a limited company buy to let mortgage basic rate taxpayer interest only, applicants must meet specific lender criteria. Unlike residential mortgages, personal income is less critical, but lenders still assess the overall financial position of the directors and shareholders.
Rental income is the primary factor in affordability assessments. Most lenders require the projected rental income to cover 125% to 145% of the mortgage interest, calculated at a stress-tested rate (typically 5.5% to 7%). For basic rate taxpayers, some lenders may use a lower stress rate, improving affordability.
The property must typically be in good condition, lettable, and meet local housing regulations. New-build flats, HMOs, and holiday lets may be subject to stricter criteria or excluded altogether. Some lenders prefer freehold houses or standard leasehold flats.
A clean credit history is essential. While minor issues may be accepted by specialist lenders, most require no recent defaults, CCJs, or missed payments. Directors must usually be aged 21 to 85 at the end of the mortgage term and either employed, self-employed, or experienced landlords.
Portfolio landlords (those with four or more mortgaged properties) face additional scrutiny. Lenders will assess the entire portfolio’s performance, including rental yields, LTV ratios, and geographic diversification. A business plan and asset and liability statement may be required (Read our guide to portfolio landlord mortgages).
Applications must be made through a limited company, ideally an SPV with a relevant SIC code such as 68209. Trading companies may be accepted but are subject to more complex underwriting. Right-to-rent compliance, landlord licensing, and fire safety regulations must all be met to qualify for lending.
Costs and Affordability
The cost of a limited company buy to let mortgage basic rate taxpayer interest only includes several components beyond the interest rate. Arrangement fees typically range from 1% to 2% of the loan amount, and some lenders charge a fixed administration fee. Valuation fees depend on property value, while legal fees are generally higher than for residential mortgages due to the corporate structure.
Interest rates for limited company BTL mortgages are slightly higher than personal name equivalents, reflecting the perceived risk. Fixed rates offer stability, while variable options may suit those expecting rate reductions.
Rental income must meet the lender’s stress-tested affordability threshold, often 125% to 145% of the interest at a notional rate. This ensures the property generates sufficient income to cover repayments even if rates rise.
Taxation is a key consideration. Limited companies are not affected by Section 24, so all mortgage interest remains deductible against rental income. However, corporation tax applies to profits, and extracting funds personally may incur additional tax.
Insurance is mandatory. Landlords must have buildings insurance and are strongly advised to take out landlord insurance, covering rent loss, liability, and property damage.
The Application Process
Applying for a limited company buy to let mortgage basic rate taxpayer interest only involves several steps:
1. Research lenders and products – compare interest rates, LTVs, and criteria.
2. Set up a limited company (if not already done) with an appropriate SIC code.
3. Consult a mortgage broker to identify suitable lenders and improve approval chances.
4. Gather documentation: company accounts, proof of identity, property details, rental projections, and existing portfolio summary (if applicable).
5. Submit a Decision in Principle (DIP) to check eligibility.
6. Complete a full mortgage application with supporting documents.
7. Arrange a property valuation and lender survey.
8. Instruct solicitors to handle legal work, including company checks and title review.
9. Receive a mortgage offer, sign contracts, and complete the purchase or remortgage.
The process typically takes 4 to 8 weeks, depending on the lender’s processing speed and the complexity of the case. Working with a specialist mortgage broker can streamline the process and improve chances of success, especially for portfolio landlords or those with unique circumstances.
Common reasons for rejection include insufficient rental income, incorrect SIC code, poor credit history, or non-compliant property types. Ensuring accurate documentation and meeting all lender criteria is essential.
Benefits, Risks and Alternatives
The main benefit of a limited company buy to let mortgage basic rate taxpayer interest only is tax efficiency. Basic rate taxpayers can fully deduct mortgage interest from rental income within a company structure, avoiding the personal tax restrictions of Section 24. Interest-only payments also reduce monthly outgoings, improving cash flow and enabling portfolio growth.
However, there are risks. Void periods, unexpected maintenance costs, and interest rate rises can impact profitability. Regulatory changes, such as EPC requirements or licensing rules, may also affect compliance and costs.
Alternative finance options include bridging loans (for short-term purchases or refurbishments), commercial mortgages (for mixed-use or multi-unit properties), and development finance (for construction projects). These may suit investors with different strategies or more complex needs.
When an existing mortgage deal ends, landlords can choose to remortgage to a new lender or take a product transfer with the current lender. Remortgaging may offer better rates or terms, while product transfers are quicker and involve less paperwork.
Frequently Asked Questions
What deposit do I need for a buy-to-let mortgage?
Most lenders require a minimum deposit of 25% for a limited company buy-to-let mortgage. However, some may ask for 30% or more, especially for specialist properties or first-time landlords. A larger deposit can help secure better interest rates and improve affordability.
Can I get limited company buy to let mortgage basic rate taxpayer interest only through a limited company?
Yes, this mortgage type is specifically designed for limited company structures. You’ll need to set up a special purpose vehicle (SPV) with a relevant SIC code for property letting. Most lenders prefer SPVs over trading companies, and the mortgage will be in the company’s name, with directors providing personal guarantees.
What rental coverage do lenders require?
Lenders typically require rental income to cover 125% to 145% of the monthly mortgage interest, calculated at a stress-tested rate (usually 5.5% to 7%). For basic rate taxpayers using a limited company, some lenders may apply a lower stress rate, making it easier to meet affordability requirements.
How does Section 24 tax affect buy-to-let mortgages?
Section 24 restricts mortgage interest relief for individual landlords, meaning they can no longer fully deduct interest from rental income. This can push basic rate taxpayers into higher tax brackets. Limited companies are exempt from Section 24, allowing full interest deduction, which is why many landlords now use company structures.
Can I live in a property with limited company buy to let mortgage basic rate taxpayer interest only?
No, you cannot live in a property financed by a limited company buy-to-let mortgage. These products are strictly for investment purposes, and lenders prohibit owner-occupation. Living in the property would breach the mortgage terms and could lead to repossession or legal action.
What credit score do I need for a buy-to-let mortgage?
Lenders prefer applicants with a good to excellent credit score, typically 650 or higher. However, specialist lenders may accept lower scores if other factors are strong, such as high rental income or a large deposit. A clean credit history with no recent defaults or CCJs is essential.
Key Takeaways
Limited company buy to let mortgage basic