Limited company buy to let mortgage accountant letter 5 year fixed is a popular financing option for landlords seeking long-term stability and tax efficiency. This mortgage type is designed for property investors who purchase or remortgage buy-to-let properties through a limited company structure. The “accountant letter” refers to a document provided by a qualified accountant verifying the company’s financial position, which some lenders require as part of the application process. The “5 year fixed” element offers predictable monthly payments and protection against interest rate fluctuations, making it attractive in today’s volatile market. As of 2025, buy-to-let lending remains competitive, with lenders offering tailored products for portfolio landlords and limited companies. This type of landlord mortgage is especially suitable for those looking to grow their investment property finance portfolio while managing taxation more efficiently under current regulations.
Quick Facts
– Interest rates: 4.5% to 6.5% (2025 average for limited company BTL)
– Minimum deposit: 25%
– Rental coverage: 125% to 145% of mortgage payments
– Maximum loan-to-value (LTV): 75%
– Arrangement fees: Typically 1% to 2% of the loan amount
– Application timeline: 4 to 8 weeks from submission to completion
Limited company buy-to-let mortgages with a 5-year fixed rate offer long-term payment certainty, especially valuable in a rising interest rate environment. Lenders assess affordability primarily based on rental income, and many require an accountant’s letter to confirm the company’s trading status and income. These mortgages are increasingly favoured by landlords seeking to mitigate the impact of Section 24 tax changes.
How This Mortgage Works
A limited company buy to let mortgage accountant letter 5 year fixed works by allowing landlords to borrow through a special purpose vehicle (SPV) or trading company rather than in their personal name. The 5-year fixed rate provides certainty over monthly repayments, which is particularly useful for financial planning and mitigating the risk of interest rate increases.
Lenders offering these products typically require a letter from a qualified accountant confirming the financial health of the limited company. This letter may include details of retained profits, director’s income, and confirmation of the company’s trading history. The fixed-rate term ensures that mortgage repayments remain stable for five years, regardless of changes in the Bank of England base rate.
This type of mortgage is well-suited for experienced landlords, portfolio investors, and those using a limited company structure to manage multiple properties. First-time landlords can also apply, though lender criteria may be more stringent. Compared to standard residential mortgages, buy-to-let lending focuses more on rental income than personal income, and affordability is assessed differently.
In 2025, lenders continue to show strong appetite for limited company BTL mortgages, especially for applicants with solid business structures and reliable rental yields. Fixed-rate products remain popular due to ongoing economic uncertainty.
Eligibility and Criteria
To qualify for a limited company buy to let mortgage accountant letter 5 year fixed, applicants must meet specific lender criteria that differ from standard residential lending.
Income Requirements:
While personal income is less critical than in residential mortgages, some lenders still require a minimum personal income (typically £25,000+) to ensure borrowers can cover property-related costs during void periods. However, many lenders focus primarily on the company’s financials, especially retained profits and rental income.
Rental Coverage and Stress Testing:
Lenders assess affordability using a rental coverage ratio, usually between 125% and 145% of the mortgage interest payments, stressed at a notional rate (often 5.5% to 6.5%). For limited companies, the stress rate may be slightly more favourable due to the absence of personal tax implications under Section 24.
Property Type Restrictions:
Most lenders prefer standard buy-to-let properties such as single-family homes and flats. HMOs (houses in multiple occupation) and multi-unit freehold blocks (MUFBs) may be accepted but often come with stricter criteria and higher interest rates.
Credit Score Expectations:
Applicants should have a good credit history with no recent defaults or CCJs. While some specialist lenders accommodate adverse credit, rates may be higher.
Age and Employment Status:
Most lenders have a minimum age of 21 and a maximum age of 85 at the end of the mortgage term. Employment status is less important if the company generates sufficient rental income, but directors must usually be UK residents.
Portfolio Landlords:
Landlords with four or more mortgaged buy-to-let properties are classified as portfolio landlords. They must provide a full portfolio schedule, business plan, and cash flow forecast. Lenders assess the overall portfolio performance and may impose stricter affordability checks (Read our guide to portfolio landlord mortgages).
Limited Company vs Personal Name:
Mortgages taken through a limited company are assessed differently from personal name applications. Lenders look at company accounts, retained profits, and director guarantees. Using a limited company can offer tax advantages, especially for higher-rate taxpayers.
Right-to-Rent and Licensing:
Applicants must ensure the property complies with Right-to-Rent checks and any local authority licensing requirements, particularly for HMOs or properties in selective licensing areas.
Costs and Affordability
When applying for a limited company buy to let mortgage accountant letter 5 year fixed, landlords should budget for several costs beyond the deposit.
Arrangement fees typically range from 1% to 2% of the loan amount, and may be added to the mortgage. Valuation fees vary depending on the property value, while legal fees are usually higher for limited company applications due to additional complexity. Broker fees may apply, especially when using a specialist adviser.
Interest rates for fixed-rate products are generally higher than variable or tracker rates, but they offer stability. In 2025, 5-year fixed BTL mortgage rates for limited companies range between 4.5% and 6.5%, depending on the lender and risk profile.
Rental income must meet the lender’s stress-tested affordability threshold. For example, a monthly rent of £1,000 must cover at least £1,250 to £1,450 of notional mortgage payments, depending on the stress rate.
Tax implications are significant. Unlike personal landlords, limited companies can still deduct mortgage interest as a business expense, avoiding the restrictions of Section 24. However, corporation tax and dividend tax apply, so professional tax advice is essential.
Landlords must also hold appropriate insurance, including buildings and landlord insurance, which may be required by the lender.
The Application Process
Applying for a limited company buy to let mortgage accountant letter 5 year fixed involves several stages:
1. Research and Pre-Qualification:
Start by identifying suitable lenders and mortgage products. A mortgage broker can help match your company profile with lender criteria.
2. Gather Documentation:
Prepare company accounts, an accountant’s letter, director ID, proof of address, business bank statements, and property details. Rental income projections or existing tenancy agreements are also needed.
3. Submit Application:
Your broker or solicitor will submit the application to the chosen lender. Some lenders require director guarantees or personal guarantees.
4. Valuation and Survey:
The lender will instruct a valuation to confirm the property’s value and rental potential. For HMOs or unusual properties, a more detailed survey may be required.
5. Underwriting and Offer:
The lender assesses the application, reviews the accountant’s letter, and performs stress testing. If approved, a formal mortgage offer is issued.
6. Legal Work and Completion:
Solicitors complete the conveyancing, company structure checks, and Companies House filings. Once all legal work is complete, funds are released.
The entire process typically takes 4 to 8 weeks. Working with a broker can speed up the process and reduce the risk of rejection.
Common reasons for rejection include insufficient rental coverage, poor credit history, or inadequate company accounts. Ensuring all documentation is accurate and up to date is essential.
Benefits, Risks and Alternatives
The main benefit of a limited company buy to let mortgage accountant letter 5 year fixed is long-term financial stability. Fixed monthly payments for five years help landlords budget effectively, while limited company ownership can offer tax advantages, particularly for higher-rate taxpayers.
There are risks to consider. If interest rates fall, you may be locked into a higher rate. Void periods can impact cash flow, and regulatory changes—such as licensing or EPC requirements—can affect profitability. Additionally, limited company mortgages often come with higher interest rates and fees.
Alternative finance options include bridging loans for short-term purchases, commercial mortgages for mixed-use properties, and development finance for refurbishment or new builds. For existing landlords, remortgaging to a new fixed rate or opting for a product transfer may be more cost-effective, depending on early repayment charges and current 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 accept slightly lower deposits for experienced landlords or high-yield properties. A larger deposit can improve your interest rate and increase the likelihood of approval.
Can I get limited company buy to let mortgage accountant letter 5 year fixed through a limited company?
Yes, many lenders offer 5-year fixed buy-to-let mortgages specifically for limited companies. You’ll typically need to set up a Special Purpose Vehicle (SPV) registered with Companies House, and provide an accountant’s letter confirming the company’s financials. This structure can be more tax-efficient for higher-rate taxpayers.
What rental coverage do lenders require?
Lenders usually require rental income to cover 125% to 145% of the mortgage payments, stress-tested at a notional interest rate (often 5.5% to 6.5%). For example, if your mortgage payment is £800/month, your rental income must be at least £1,000 to £1,160 per month. Limited company applications may benefit from slightly lower stress rates.
How does Section 24 tax affect buy-to-let mortgages?
Section 24 restricts individual landlords from deducting mortgage interest from rental income for tax purposes. This can significantly increase tax liabilities for higher-rate taxpayers. Limited companies are not affected