Ltd Company Buy-to-Let Mortgages Explained: SPV Structures for Landlords

Since the phased introduction of mortgage interest tax relief restrictions between 2017 and 2020, an increasing number of landlords have turned to limited company structures for their buy-to-let investments. Purchasing through a Special Purpose Vehicle (SPV) — a limited company set up specifically to hold property — offers tax advantages that can significantly improve returns, particularly for higher-rate taxpayers. In this guide, we explain everything you need to know about limited company buy-to-let mortgages, from the mechanics of SPV structures to the lender criteria, costs, and important considerations before making the switch.

What is an SPV and why do landlords use them?

An SPV (Special Purpose Vehicle) is a limited company formed specifically for the purpose of purchasing and managing buy-to-let property. Unlike a trading company, which might carry on various business activities, an SPV’s articles of association and business activities are limited to property investment and related activities.

The primary reason landlords use SPVs is the tax treatment of mortgage interest. When you own a buy-to-let property personally, you can no longer deduct mortgage interest from your rental income before calculating tax. Instead, you receive a 20% tax credit on the interest paid. This means that if you are a 40% or 45% taxpayer, you are effectively paying significantly more tax on your rental income than you did under the old rules.

Within a limited company, mortgage interest remains fully deductible against rental profits before corporation tax is calculated. Corporation tax is currently charged at 25% for companies with profits over £250,000, and at lower effective rates for smaller profits through the marginal relief system.

Here is a simplified example comparing the two structures for a higher-rate taxpayer:

Personal ownership:

• Rental income: £15,000
• Mortgage interest: £8,000
• Other expenses: £2,000
• Taxable rental profit: £13,000 (rental income minus expenses, but mortgage interest not deductible)
• Tax at 40%: £5,200
• Less 20% tax credit on mortgage interest: -£1,600
• Net tax: £3,600

Limited company ownership:

• Rental income: £15,000
• Mortgage interest: £8,000
• Other expenses: £2,000
• Taxable rental profit: £5,000 (all expenses deductible including mortgage interest)
• Corporation tax at 25%: £1,250
• Net tax: £1,250 (before any personal tax on profit extraction)

The saving of £2,350 per property is significant, though it is important to note that extracting profits from the company via salary or dividends triggers additional personal tax, which reduces the overall advantage. Professional tax advice is essential to model the full picture for your circumstances.

How do limited company buy-to-let mortgages work?

Limited company buy-to-let mortgages work similarly to personal buy-to-let mortgages in terms of the property purchase process, but there are some key differences.

The borrower — the mortgage is in the name of the limited company, not in your personal name. However, the company directors (and sometimes shareholders) are required to provide personal guarantees, meaning you are still personally liable if the company defaults on the mortgage.

SPV requirements — most lenders require the company to be structured as an SPV with Standard Industrial Classification (SIC) code 68100 (buying and selling of own real estate) or 68209 (other letting and operating of own or leased real estate). The company’s articles of association should reflect property investment activities.

Director assessment — lenders assess the personal circumstances of the company directors, including credit history, income, and experience. This is because the personal guarantee means the directors’ financial stability is relevant to the lending decision.

Rental income assessment — the ICR requirements are the same as for personal buy-to-let. The rental income must typically cover 125% of the mortgage payment at a stress-tested rate. Some lenders apply a lower ICR for limited company applications, recognising the tax efficiency of the structure.

Interest rates — limited company buy-to-let mortgage rates have historically been slightly higher than personal buy-to-let rates, though the gap has narrowed significantly in recent years. The premium is typically 0.1% to 0.5% above equivalent personal rates.

Deposit — minimum deposit requirements are typically the same as personal buy-to-let (25%), though some products may require more.

Setting up an SPV for buy-to-let

If you decide to purchase through a limited company, the setup process is relatively straightforward.

Company formation — you can form a limited company through Companies House for as little as £12 online. Choose a company name, appoint directors and shareholders, and register the company with the appropriate SIC codes.

SIC codes — as mentioned, use 68100 and/or 68209. Some lenders have specific SIC code requirements, so check with your broker before registering.

Bank account — open a business bank account for the company. Rental income and mortgage payments should flow through this account.

Accounting — you will need an accountant to prepare annual accounts and file the corporation tax return. Budget £500 to £1,500 per year for accounting costs, depending on the complexity of your affairs.

Company administration — limited companies have ongoing filing obligations, including annual confirmation statements to Companies House and corporation tax returns to HMRC.

Your mortgage broker at Option Finance can advise on the specific setup requirements that lenders look for, ensuring your company is structured correctly from the start. For a broad understanding of the buy-to-let market, our buy-to-let service page covers all the key areas.

Who benefits most from limited company ownership?

The tax benefits of limited company ownership are not equally distributed across all landlords. The following groups typically benefit most:

Higher-rate and additional-rate taxpayers — if your combined income (including rental profits) pushes you into the 40% or 45% tax brackets, the impact of the mortgage interest relief restriction is most severe, making the limited company route most attractive.

Landlords with significant mortgage debt — the larger the mortgage interest costs, the greater the tax saving within a company structure. If your properties are owned outright or have very small mortgages, the benefit is minimal.

Portfolio landlords — if you own multiple properties, the cumulative tax saving across the portfolio can be substantial. Even a relatively modest per-property saving multiplied across a portfolio of five, ten, or more properties becomes very significant. Portfolio landlords face specific lender criteria that specialist brokers understand well.

New investors — if you are starting your buy-to-let journey, purchasing through a company from the outset avoids the complications and costs of transferring properties later.

Landlords planning long-term growth — if you intend to hold properties long-term and reinvest profits into additional purchases, a company structure allows profits to be retained and reinvested at a lower effective tax rate.

Conversely, basic-rate taxpayers with one or two properties and small mortgages may find that the additional costs and administrative burden of a company structure outweigh the tax benefits.

Transferring existing properties to a limited company

One of the most common questions we receive is whether existing personally owned properties should be transferred to a limited company. The answer requires careful analysis because the transfer process triggers several costs:

Stamp duty — transferring a property to a company is treated as a sale, even if the company is owned by the same person. The company must pay stamp duty on the purchase, including the 5% additional property surcharge. Use our stamp duty calculator to estimate this cost.

Capital gains tax — the transfer is treated as a disposal at market value for CGT purposes. If the property has increased in value since you bought it, you will owe CGT on the gain (18% or 24% depending on your tax band, with a £3,000 annual allowance).

Legal costs — the transfer requires conveyancing work as if it were a standard property sale and purchase.

New mortgage — the company will need a new mortgage, as personal buy-to-let mortgages cannot be transferred to a company. This means arrangement fees, valuation fees, and potentially higher interest rates.

SDLT considerations — if you transfer multiple properties, some tax advisers use structures like partnership incorporations to mitigate SDLT costs, but these are complex and should only be undertaken with specialist tax advice.

Given these costs, transferring existing properties only makes financial sense if the ongoing tax savings will outweigh the one-off transfer costs within a reasonable timeframe. For most landlords, it is more practical to keep existing properties in personal ownership and purchase new properties through a company going forward.

Lender criteria for limited company buy-to-let

The number of lenders offering limited company buy-to-let mortgages has grown substantially in recent years. Key criteria include:

Company structure — the company should be an SPV with the correct SIC codes. Trading companies (those with other business activities) face more limited options and stricter criteria.

Directors — lenders assess the directors’ personal credit history, income, and property experience. All directors typically need to provide personal guarantees.

Shareholders — some lenders have requirements about who can be a shareholder. Corporate shareholders (another company owning shares in the SPV) are accepted by some lenders but not others.

Number of properties — portfolio landlords (four or more mortgaged properties) face additional scrutiny, with lenders reviewing the entire portfolio. Portfolio requirements become even more important when purchasing through a limited company structure.

Property type — most lenders accept standard residential property, but HMOs, multi-unit freehold blocks, and holiday lets may require specialist products. Different property types may also affect whether limited company ownership is the right structure.

Minimum income — many lenders require directors to have a minimum personal income, typically £25,000.

Adverse credit — director credit issues are assessed similarly to personal buy-to-let applications. Some specialist lenders consider applications where directors have adverse credit, though options are more limited.

Running costs of a limited company

Operating a limited company involves ongoing costs that need to be factored into your investment calculations:

• Accountancy fees: £500 to £1,500 per year (more for complex portfolios)
• Corporation tax return: Usually included in accountancy fees
• Companies House confirmation statement: £13 per year
• Business bank account fees: Variable, some accounts are free
• Personal tax return: If you extract income through salary or dividends, you may need to file a personal return (which you may already do)
• Professional advice: Periodic reviews of your tax position and company structure

These costs might total £800 to £2,000 per year for a simple SPV with a few properties. While this is an additional expense compared to personal ownership, the tax savings typically outweigh these costs for landlords who fit the profile described above.

Extracting profits from the company

Profits retained in the company are subject to corporation tax, but extracting those profits to your personal bank account triggers additional tax. The main methods of extraction are:

Dividends — the most common method. After corporation tax, profits can be distributed as dividends. You receive a £1,000 tax-free dividend allowance, and dividends above this are taxed at 8.75% (basic rate), 33.75% (higher rate), or 39.35% (additional rate).

Salary — paying yourself a salary from the company is deductible against the company’s profits, reducing corporation tax. However, salary is subject to income tax and National Insurance (both employer and employee). Many landlords pay a small salary up to the NI threshold and take the rest as dividends.

Director’s loan — you can lend money to the company (e.g., for the deposit) and have it repaid without tax consequences. However, the company borrowing from a director (drawing money out as a loan) has specific tax rules that need to be followed carefully.

Professional tax advice is essential to determine the most tax-efficient extraction strategy for your circumstances. The interaction between corporation tax, dividend tax, and your other personal income is complex.

Is limited company buy-to-let right for you?

The decision to use a limited company for buy-to-let investment is a significant one with long-term implications. It is not a decision to make based on a single article or a conversation with a friend who has done it. Every landlord’s tax position, portfolio size, and investment goals are different.

Key questions to consider:

• What is your personal income tax rate?
• How much mortgage interest do you pay across your portfolio?
• How many properties do you plan to acquire in the future?
• Do you plan to hold properties long-term or sell within a few years?
• Can the ongoing administrative costs be justified by the tax savings?
• Have you taken professional tax advice specific to your circumstances?

For comprehensive guidance on the broader buy-to-let landscape, our ultimate UK buy-to-let mortgage guide covers all aspects of buy-to-let investment. You might also find our mortgage calculator and affordability calculator useful for modelling different scenarios. If you’re currently remortgaging your portfolio, our remortgage calculator can help compare switching costs and savings.

Get expert advice on limited company mortgages

At Option Finance, we have extensive experience arranging limited company buy-to-let mortgages. Our advisers understand the SPV market, know which lenders offer the most competitive rates, and can guide you through the entire process — from company formation to mortgage completion.

Whether you are making your first purchase through a limited company or refinancing an existing portfolio, we are here to help. Apply now to speak with one of our specialist advisers and find out whether a limited company structure is right for your buy-to-let investments.