Limited company buy to let mortgage best rates interest only products have become increasingly popular among UK landlords and property investors in 2025. These specialist landlord mortgages are designed for those who purchase rental properties through a limited company structure, rather than in their personal name. The appeal lies in potential tax efficiencies, simplified portfolio management, and access to competitive BTL mortgage rates — particularly on an interest-only basis, which helps maximise monthly cash flow.
With rising interest rates and tighter affordability checks, many landlords are seeking the best interest-only buy-to-let lending options available through limited companies. These mortgages allow landlords to pay only the interest each month, with the capital repaid at the end of the term — freeing up rental income for reinvestment or other expenses. As regulations and taxation on personally held properties continue to tighten, limited company buy-to-let mortgages offer a strategic alternative for serious investors.
Quick Facts
– Interest rates: Typically between 4.5% and 6.5% (as of early 2025)
– Minimum deposit: 25% (some lenders may require more for complex cases)
– Rental coverage: 125% to 145% at a stress-tested interest rate (usually 5.5% or higher)
– Maximum loan-to-value (LTV): Up to 75%
– Arrangement fees: Often 1% to 2% of the loan amount
– Application timeline: 4 to 8 weeks on average
Limited company buy-to-let mortgages require careful planning. Lenders assess both the company and the directors, and affordability is based on projected rental income. Interest-only options are common, helping landlords manage cash flow, but they come with long-term repayment considerations.
How This Mortgage Works
A limited company buy to let mortgage best rates interest only is a mortgage product designed for landlords purchasing or remortgaging rental properties through a Special Purpose Vehicle (SPV) limited company. The mortgage is registered in the company’s name, but directors and shareholders are usually required to provide personal guarantees.
These mortgages are typically structured as interest-only, meaning landlords pay only the interest each month, not the capital. This keeps monthly payments lower, allowing investors to retain more of their rental income. The capital is repaid at the end of the mortgage term, often through sale or remortgage.
Product types include fixed-rate deals (commonly 2, 5, or 10 years), variable rates, and tracker mortgages. Fixed-rate products are popular in 2025 due to interest rate volatility, providing payment certainty.
This mortgage suits portfolio landlords, higher-rate taxpayers, and those scaling their property business. First-time landlords can also apply, though criteria may be stricter. Lender appetite for limited company lending remains strong, with many specialist lenders active in the market. Compared to residential mortgages, buy-to-let lending is assessed on rental income rather than personal earnings, and affordability is stress-tested accordingly.
Eligibility and Criteria
To qualify for a limited company buy to let mortgage best rates interest only, landlords must meet both company and individual criteria. While the mortgage is taken out in the name of the limited company, lenders assess the directors’ financial background and experience.
Income requirements: Most lenders do not require a minimum personal income for limited company BTL mortgages, but some prefer directors to earn £25,000+ per year. Others focus solely on the rental income of the property.
Rental coverage: Lenders use an Interest Coverage Ratio (ICR) to assess affordability. This is typically 125% to 145% of the monthly mortgage payment, calculated at a stress-tested rate of 5.5% to 8%, depending on the lender and product type. For example, a monthly mortgage payment of £1,000 would require rental income of at least £1,250 to £1,450.
Property type: Standard buy-to-let properties such as single-family homes and flats are widely accepted. Some lenders restrict HMOs (houses in multiple occupation), new builds, or properties above commercial premises. Others specialise in complex property types.
Credit score: A good credit history is essential. Most lenders require no recent defaults or CCJs. A credit score above 650 is typically expected, though criteria vary.
Age and employment: Most lenders accept applicants aged 21 to 85. Employment status is less critical than rental income, but self-employed directors may need to show business accounts.
Portfolio landlords: Those with four or more mortgaged properties are subject to additional scrutiny. Lenders may require a business plan, cash flow forecasts, and details of the entire portfolio (Read our guide to portfolio landlord mortgages).
Limited company structure: Most lenders require the company to be an SPV registered with SIC codes such as 68209 (Other letting and operating of own or leased real estate). Trading companies may face more limited options.
Regulatory compliance: Properties must meet all local authority licensing requirements and right-to-rent checks. Non-compliance can lead to mortgage refusal.
Costs and Affordability
Limited company buy-to-let mortgages come with several costs that landlords must budget for:
– Arrangement fees: Typically 1% to 2% of the loan amount, often added to the mortgage
– Valuation fees: £300 to £1,000 depending on property value
– Legal fees: £1,000 to £2,000 for limited company conveyancing
– Broker fees: £500 to £1,500 depending on complexity
Interest rates vary by lender and product. Fixed rates offer stability, while variable and tracker rates may be lower initially but are subject to change.
Rental income is the primary affordability metric. Lenders assess whether the rent covers the mortgage payments with a safety margin (ICR). Stress testing ensures landlords can afford repayments even if interest rates rise.
Taxation is a key consideration. Limited companies can deduct mortgage interest as a business expense, unlike individual landlords affected by Section 24. However, corporation tax and dividend tax must be factored in (Read our guide to buy-to-let taxation changes).
Insurance is mandatory. Buildings insurance is required, and landlord insurance is strongly recommended.
The Application Process
Securing a limited company buy to let mortgage best rates interest only involves several key steps:
1. Research and planning: Identify suitable lenders or work with a specialist broker who understands limited company lending.
2. Company setup: Ensure your SPV is correctly registered with appropriate SIC codes. Prepare your business plan if required.
3. Documentation: Provide proof of ID, address, company registration details, director information, business bank statements, and rental income projections.
4. Mortgage application: Submit your application through a broker or directly to the lender. Include property details and letting agent estimates.
5. Valuation: The lender instructs a surveyor to assess the property’s value and rental potential.
6. Underwriting: The lender reviews your application, credit history, and affordability. This may take 2 to 6 weeks depending on complexity.
7. Offer and legal work: Once approved, the lender issues a mortgage offer. Your solicitor handles conveyancing and company checks.
8. Completion: Funds are released and the property purchase or remortgage is finalised.
Working with a broker can significantly improve your chances of approval, especially for complex cases. Common reasons for rejection include insufficient rental income, poor credit history, or incorrect company setup.
Benefits, Risks and Alternatives
Limited company buy to let mortgage best rates interest only products offer several advantages:
– Tax efficiency: Mortgage interest is fully deductible for limited companies
– Cash flow: Interest-only payments free up rental income
– Portfolio growth: Easier to manage multiple properties under one entity
– Separation of liability: Company structure protects personal assets
However, there are risks:
– Void periods: No tenants means no income to cover mortgage payments
– Interest rate rises: Payments may increase significantly on variable deals
– Regulatory changes: Tax rules and licensing requirements can shift
– Exit strategy: Repaying the capital at term-end requires planning
Alternatives include bridging loans (for short-term finance), commercial mortgages (for mixed-use or semi-commercial properties), and development finance (for refurbishment or new builds). For current landlords, remortgaging into a new fixed-rate deal may offer better value than a product transfer, depending on fees and rates.
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 specialist lenders may ask for 30% or more, particularly for HMOs or non-standard properties. A larger deposit can help secure better interest rates and improve your chances of approval.
Can I get a limited company buy to let mortgage best rates interest only through a limited company?
Yes, many UK lenders now offer interest-only buy-to-let mortgages to limited companies, particularly SPVs set up solely for property investment. These mortgages are assessed based on rental income and company structure, and directors usually provide personal guarantees.
What rental coverage do lenders require?
Lenders typically require rental income to cover 125% to 145% of the mortgage payment, stress-tested at a notional interest rate (often 5.5% to 8%). This ensures the property remains affordable even if rates rise. For example, a £1,000 monthly mortgage might require £1,250 to £1,450 in monthly rent.
How does Section 24 tax affect buy-to-let mortgages?
Section 24 restricts mortgage interest tax relief for individual landlords, increasing their tax liability. Limited companies are exempt from Section 24, allowing them to deduct mortgage interest as a business expense. This makes limited company structures more tax-efficient for higher-rate taxpayers.
Can I live in a property with a limited company buy to let mortgage best rates interest only?
No, you cannot live in a property financed with a buy-to-let mortgage, whether through a limited company or personal name. These mortgages are for rental properties only. Living in the property would breach the mortgage terms and could lead to repossession.
What credit score do I need for a buy-to-let mortgage?
Most lenders prefer applicants with a credit score of 650