The incorporation question has become more pressing since Section 24 removed full mortgage interest deductibility from personal landlords in 2020. For higher-rate taxpayers, the restriction is not merely inconvenient — it means paying income tax on a portion of the mortgage interest that represents no actual profit, effectively creating a tax liability on turnover rather than earnings. It is the single most frequently cited driver behind landlords exploring limited company structures.
That observation is accurate. What is less frequently noted is that the tax advantage of operating through a company is context-dependent, that higher mortgage rates on company borrowing frequently offset a significant portion of the tax saving, and that the cost of transferring existing properties into a company — through Stamp Duty Land Tax and capital gains on disposal — makes retrospective incorporation materially expensive for landlords who already hold a portfolio personally. The question of whether to incorporate is not whether companies pay less tax in the abstract. It is whether incorporation improves the financial outcome for a specific landlord with a specific portfolio at a specific point in time.
Where Does Incorporation Provide a Genuine Advantage?
The primary advantages are tax-structural. A limited company can deduct mortgage interest as a business expense in full — unlike personal landlords operating under Section 24, who receive only a 20% tax credit. Where a landlord pays higher or additional rate income tax, the difference in effective tax treatment can be substantial per property, and the gap widens as portfolio income grows.
Company profits are subject to corporation tax — currently 25% for profits above £250,000 and 19% for smaller companies. A higher-rate personal taxpayer currently pays 40% on the same income — rising to 42% from April 2027 under the separate property income rates legislated in the Finance Act 2026. Where profits are retained in the company and reinvested into further acquisitions rather than extracted personally, the tax deferral compounds significantly over time. This is the scenario in which incorporation most clearly justifies its costs and complexity.
| Factor | Personal Ownership | Limited Company |
|---|---|---|
| Mortgage interest | 20% tax credit only — Section 24 | Full deduction as a business expense |
| Tax rate on profits | 40% higher rate (42% from April 2027); 45%/47% additional | 25% corporation tax; 19% for smaller profits |
| Profit reinvestment | Taxed immediately as personal income | Retained and reinvested tax-deferred; taxed on extraction |
| Mortgage rates | Standard BTL rates | Typically 0.5–1.5% higher; personal guarantees usually required |
| Accounting burden | Annual self-assessment return | Annual accounts, CT600, confirmation statements — materially higher cost |
| Transfer of existing properties | No tax trigger | SDLT and CGT on disposal to company — potentially prohibitive |
Where Are the Genuine Disadvantages?
The structural advantages of incorporation are real, but they come with corresponding costs. Company buy-to-let mortgages carry rates typically 0.5% to 1.5% above equivalent personal products, and personal guarantees are almost universally required — which means the liability protection that is often cited as a benefit of limited liability is, in the majority of cases, neutralised before the company acquires its first property.
Extracting profits from a company, through salary, dividends, or a combination, triggers personal tax liability. The headline advantage of corporation tax over income tax is real for retained profits. For profits that are extracted to fund personal living costs, the combined effect of corporation tax and dividend tax frequently produces an effective rate comparable to, or in some cases exceeding, the personal tax position on the same income. The advantage lies in the deferral and the reinvestment cycle, not in the extraction.
Landlords who already own properties personally and are considering transferring them into a company face two simultaneous tax events: Stamp Duty Land Tax on the company's acquisition, and capital gains tax on the individual's disposal. Where properties have appreciated significantly, this cost can run to tens of thousands of pounds per property — making retrospective incorporation financially unattractive for most established portfolios.
The administrative overhead of a limited company is also a genuine cost, not a theoretical one. Annual statutory accounts, a Corporation Tax return, a confirmation statement, and the accountancy fees associated with all three are recurring obligations that do not exist for a personal landlord operating through self-assessment. For a portfolio generating modest surplus, these costs can consume a meaningful share of any tax saving.
Is Incorporation the Right Decision for Your Portfolio?
Incorporation tends to make strategic sense for landlords building a portfolio from scratch who intend to retain profits for reinvestment, who are higher or additional rate taxpayers with four or more properties, and whose long-term plan is portfolio growth rather than extraction and wind-down. The structure rewards patience and scale. From April 2027, with personal property income rates rising to 42% for higher-rate taxpayers, the gap between personal and corporate tax treatment widens further — making the incorporation question more pressing for landlords who have not yet considered it carefully.
The decision should be modelled specifically, not decided generically. A landlord with two properties generating modest surplus, where the mortgage rate premium on a company structure exceeds the Section 24 saving, will see no financial benefit from incorporation. A landlord building a ten-property portfolio with significant retained profits will likely see a meaningful advantage over time. The same question produces different answers depending on the numbers.
Incorporation is also not the permanent, irreversible decision it is sometimes presented as. The structure can be reviewed as the portfolio evolves — though changes carry their own tax costs, and frequent restructuring is rarely efficient. The more practical approach is to model the decision correctly at the outset, using realistic assumptions about growth, extraction, and financing costs, and to review annually whether the structure continues to serve the strategy.
Professional advice from an accountant who specialises in property investment is not optional here. The interaction between Section 24, corporation tax, dividend tax, mortgage rate differentials, and capital events on eventual disposal is sufficiently complex that a generic answer produces a misleading one. The question is straightforward. The answer, properly calculated, almost never is.
This article reflects our understanding of the law at the time of publication. It is for general guidance only and does not constitute legal advice. Always verify against GOV.UK or seek qualified legal advice before acting.
