A UK property portfolio benefits from a corporate or SPV structure once finance costs become material to net yield, the portfolio reaches roughly four to six properties, or the owner is approaching a wealth-transfer or exit decision. Below those thresholds the additional administrative cost rarely pays for itself. Above them the cost of staying personally held usually does.
In this article
- Why does corporate structure matter for a property portfolio?
- What are the decision thresholds?
- What reliefs make the move possible?
- What are the costs that catch landlords out?
- Should each property sit in its own SPV?
- What are the most common mistakes?
Why does corporate structure matter for a property portfolio?
The decision was settled for most landlords by the Section 24 mortgage interest restriction introduced from 2017. Personal landlords lose the ability to deduct mortgage interest as a normal expense and instead receive a 20% basic-rate credit. For higher-rate taxpayers with leveraged portfolios, this changed the after-tax economics fundamentally. Corporates retained full interest deductibility against profits.
The corporate route is not automatically better. It introduces double tax (corporation tax then dividend or gain on extraction), removes the personal CGT annual exempt amount, and adds compliance cost. The decision is whether the interest-relief benefit and structural advantages outweigh those costs at the portfolio's specific scale.
What are the decision thresholds?
Three thresholds typically tip the decision. Annual mortgage interest above £25k where the owner is in the higher or additional rate band, the Section 24 cost becomes material. Portfolio of four or more properties with active expansion plans, corporate finance options widen and SPV structures become more efficient. Owner approaching 60 with succession or sale planning ahead, corporate ownership offers more flexible wealth-transfer routes.
None of the three is an absolute trigger. The combined picture matters. A 35-year-old higher-rate landlord with three properties and £80k of annual interest is in a different position from a 65-year-old basic-rate landlord with eight properties owned outright. The structure should fit the owner, not the other way around.
What reliefs make the move possible?
The two principal reliefs are Section 162 incorporation relief and SDLT incorporation relief for partnerships. Section 162 defers the personal CGT that would otherwise crystallise on transferring a property business into a company. SDLT relief is more constrained and depends on the existence of a genuine partnership structure pre-incorporation, plus meeting connected-party rules.
Crucially, both reliefs require that the activity is a property business in HMRC's terms, not just a passive investment. The bar is meaningful: the landlord must be substantively involved in management, with significant time committed, not simply holding a managed portfolio. Incorporations that fail this test trigger immediate CGT and SDLT charges that can wipe out years of tax benefit. According to the 2024 ICAS property tax survey, around 19% of incorporations reviewed by professional advisers had insufficient evidence of partnership status, leaving the SDLT relief vulnerable to challenge.
What are the costs that catch landlords out?
The visible costs are easy: incorporation, valuation, legal work, and the new corporate compliance cycle. The invisible costs catch more landlords out. Refinance is required because most personal mortgages cannot be ported to a limited company; the new BTL company rates are usually 50-150 basis points higher. Lender legal and arrangement fees recur on each refinance. Director's loan accounts replace what used to be personal capital, and extracting value later runs into dividend tax or salary NIC.
The recurring corporate compliance cost, accounts, corporation tax return, ATED if applicable, confirmation statements, is typically £2k to £5k a year per company. Multiply by the number of SPVs and the management overhead becomes material.
Should each property sit in its own SPV?
Lenders prefer it for risk isolation. Owners often resist it for cost. The answer depends on the portfolio. Single-SPV-per-property structures isolate risk cleanly: a default on one property does not cascade to the others. They make individual property sales easier, the buyer purchases the SPV's shares, avoiding SDLT on the property itself for the buyer (though anti-avoidance rules apply). They also enable per-property gearing strategies.
Against that, each SPV adds £2k-£5k a year of compliance, plus the inter-company complexity of moving cash between entities. For portfolios of four or more properties with growth plans and external lender involvement, SPV-per-property usually pays for itself. For three or fewer properties or a static portfolio, a single holding company is often more efficient.
What are the most common mistakes?
The biggest mistake is deferring the decision until incorporation is forced by an external event, a refinance the lender will not roll over personally, a tax investigation, or an inheritance trigger. Incorporating under time pressure rarely captures the full benefit of the available reliefs because evidence has to be assembled retrospectively. The second mistake is incorporating without a clear extraction strategy, leaving owners with retained corporate profits that are taxed twice if eventually paid out.
The third mistake is treating SPVs as administrative wrappers rather than genuine corporate vehicles. SPVs need real governance: minutes, separate bank accounts, formal agreements between connected parties, and clean accounting. HMRC's challenges to property structures almost always start with whether the corporate form has been respected in practice. Where it has not, the protection it appears to offer evaporates.
Written by Bharat Varsani FCCA. Director of Key Ledgers Global, currently operating at CFO level within a 15-entity care and property group with £205m of assets under management, 500+ properties and a multi-SPV financing structure. 20+ years of forensic and CFO experience.
Sources: ICAS UK Property Tax Survey 2024 for the cited 19% partnership-evidence figure; HMRC PIM4500 series guidance on property businesses and Section 162 incorporation relief.
Frequently asked questions
Does Section 24 still apply to all personally-held property in 2026?
Yes. The mortgage interest restriction enacted from 2017 remains in force. Personally-held residential property generates a basic-rate (20%) credit on mortgage interest rather than a deduction against rental profits. The position is unchanged for FY 2026.
Can I transfer my existing personal portfolio into a company without paying CGT?
Section 162 incorporation relief defers the CGT if the conditions are met, principally that the activity qualifies as a property business and the entire business is transferred in exchange for shares. The relief is deferral, not exemption. CGT crystallises later on disposal of the shares.
How does ATED affect SPV structures?
ATED applies to companies holding residential properties valued above £500k that are not let on commercial terms. Most BTL SPVs are exempt because they let on commercial terms, but the annual return is still required. Failure to file triggers penalties even where no tax is due.