Somewhere in the last decade, "buy it through a company" went from niche advice to the default answer on every property forum. Sometimes it is the right call. Sometimes it quietly costs the owner money for years. The honest answer is that it depends — and it is worth understanding what it depends on.
Why the question even comes up
For most of modern history, a private landlord could deduct mortgage interest from rental income before working out their tax bill. That changed. Individuals can no longer treat mortgage interest as a straightforward expense — instead, relief is given as a basic-rate tax reduction.
For a basic-rate taxpayer, the effect is modest. For a higher or additional-rate taxpayer, it can be severe: you are taxed on rental income at your marginal rate, but only get relief on the interest at the basic rate. In a highly geared portfolio, it is entirely possible to be taxed on a "profit" that is larger than the cash you actually kept.
A limited company is not subject to that restriction. Inside a company, mortgage interest is simply a cost of doing business, deducted in full before tax. That single difference is what drives most of the interest in company ownership.
How a company changes the maths
A company pays corporation tax on its profits (currently between 19% and 25%, depending on the level of profit) rather than income tax. For a landlord who would otherwise be paying 40% or 45% on rental income, the headline rate inside a company looks attractive — and because interest is fully deductible, the profit being taxed is genuinely lower too.
But there is a catch that the forum advice often skips: the money is taxed twice. Once as profit inside the company, and again when you take it out personally — usually as a dividend. So the relevant comparison is never just "corporation tax versus income tax." It is the combined cost of earning the profit and getting it into your own bank account.
This is why company ownership tends to suit one situation in particular: when you do not need the income now. If profits stay inside the company and are reinvested into the next deposit, that second layer of tax is deferred — sometimes for years. The company becomes a compounding machine. If you need the rent to live on every month, much of the advantage erodes.
The costs of getting in — and out
A company is cheap to start and not cheap to unwind. Before committing, the costs worth pricing in include:
- Moving an existing property in. Transferring a property you already own personally into a company is a sale in the eyes of HMRC. That can trigger capital gains tax on the gain and stamp duty for the company buyer, both calculated on market value — even though no money has changed hands with a third party.
- The additional-property surcharge. A company buying residential property pays the stamp duty surcharge on additional dwellings, just as an individual second-property buyer would.
- Mortgage pricing. Lending to a company (often a special purpose vehicle, or SPV) has historically carried higher rates and fewer products than personal buy-to-let, though the gap has narrowed.
- Running costs. Annual accounts, a corporation tax return, a confirmation statement, and bookkeeping. Modest, but real, and they recur every year.
None of these are dealbreakers. But they mean a company rarely pays off on a single property you intend to hold briefly. The structure rewards scale and patience.
So when does it actually make sense?
As a rough guide, company ownership tends to work in your favour when several of these are true:
- You are a higher or additional-rate taxpayer, so the interest-relief restriction bites hard.
- You are building a portfolio rather than buying one property, and you intend to keep reinvesting.
- You do not need to draw the rental profit personally in the short term.
- You are thinking in decades, not years — including how the asset eventually passes to family.
It tends to work against you when you are a basic-rate taxpayer, when you are buying one property mortgage-free, or when the rent is income you need to spend now.
The decision is not only about tax
It is easy to treat this as a spreadsheet exercise. It is not quite. A company changes how you raise finance, how visible your affairs are, how you bring in a partner or investor, and how the assets are dealt with on death. Two investors with identical numbers can correctly reach opposite decisions because their plans for the next twenty years are different.
That is the real work: not finding the lower tax rate, but matching the structure to what you are actually trying to build. Get it right at the outset and it compounds quietly in your favour. Get it wrong and the cost of correcting it — the tax on unwinding — is exactly the friction that kept you stuck.
Before you decide
If you are weighing up your first investment property, or wondering whether an existing portfolio is sitting in the wrong structure, this is precisely the kind of question worth an hour with a specialist before you commit. Our property developer and investor advisory service exists for exactly this — structure, SDLT, CGT and the long view — and you can tell us your situation here.
This article is general information, not personal tax advice, and tax rules change. Your own position depends on facts we cannot see from here — please take advice before acting on anything above.