A client called last month, excited about forming a limited company for his next buy-to-let purchase. His accountant had run the numbers on corporation tax versus income tax, and the savings looked compelling. "It's a no-brainer," he said. "Everyone's doing it now."

I asked him one question: "Have you checked what lenders will actually offer your new company?"

The conversation that followed illustrates why the limited company route for buy-to-let — while potentially beneficial — deserves more scrutiny than the tax savings headlines suggest.

The Lender Mathematics Don't Always Add Up

This particular client owned two rental properties in his personal name and wanted to purchase a third. On paper, the special purpose vehicle (SPV) route made sense. As a higher-rate taxpayer earning £65,000 annually, plus rental income, he faced higher-rate income tax on rental profits versus corporation tax — the rates for the current tax year are published by HMRC on gov.uk, and which applies to you is a question for your accountant.

But lenders view limited company applications differently. Where his personal applications might access a far wider range of buy-to-let products, the SPV route narrowed the choice considerably. Limited-company rates are often a little higher than personal ones.

That difference adds to the annual cost, and whether the structure suits you is a question for your accountant. Set against potential tax savings of £1,800 per year on a £200 monthly rental profit, the margin for error becomes uncomfortably thin. Factor in accountancy fees for the limited company — typically £1,000–£2,000 annually — and the arithmetic shifts further.

Your home may be repossessed if you do not keep up repayments on your mortgage.

Why Lenders Price SPV Mortgages Differently

The reluctance isn't arbitrary. Lenders perceive additional complexity with limited company lending. Recovery procedures if things go wrong involve corporate insolvency rather than personal bankruptcy — a different legal framework with different timescales.

Many lenders also require personal guarantees from company directors, which somewhat defeats the limited liability purpose. Others insist the company holds no other assets, creating practical constraints for portfolio expansion.

The underwriting process typically takes longer too. Where a personal buy-to-let application might complete in four weeks, SPV applications often stretch to six or eight weeks. Lenders want to see properly drafted articles of association, sometimes requiring specific clauses about property investment activities.

Some lenders won't touch SPVs at all. Others will consider them only above certain loan amounts — often £150,000 or £200,000 minimum. This immediately rules out many first-time landlords or those buying in lower-value regions.

When the SPV Route Makes Sense

Despite these challenges, limited company structures can prove worthwhile. The tax advantages become more pronounced for additional-rate taxpayers. Corporation tax still offers meaningful savings against higher rates of income tax; the rates for the current tax year are published by HMRC on gov.uk. Speak to an accountant before you decide.

Inheritance tax planning provides another angle. Properties held in limited companies don't form part of personal estates, potentially saving inheritance tax on substantial portfolios — the thresholds for the current tax year are published by HMRC on gov.uk, and this is a question for your accountant. For landlords building significant property wealth, this consideration often outweighs the mortgage rate premium.

The flexibility for profit extraction also matters. Limited companies can retain profits for future investment without the owner paying immediate tax, then distribute dividends when tax-efficient to do so. This becomes particularly valuable for portfolio landlords reinvesting rental profits into additional properties.

My client's decision ultimately came down to a five-year plan. His accountant confirmed the tax savings would compound over time, especially as rental yields increased. The rate premium would remain static while tax savings grew with rental income and his personal earnings.

He proceeded with the SPV, accepting the narrower lender choice and higher rate as the price for long-term tax efficiency. But the decision was informed rather than automatic.

The Practical Reality

The limited company route for buy-to-let mortgages isn't inherently better or worse — it's different, with trade-offs that vary by individual circumstances. The tax savings are real but often overstated in isolation. The mortgage market reality is more restrictive and expensive than many investors expect.

Before committing to the SPV route, consider the full picture: current and projected income tax rates, mortgage rate premiums, ongoing accountancy costs, and the practical limitations of fewer lender options. Run scenarios over multiple years rather than focusing solely on immediate tax benefits.

Most importantly, secure mortgage agreement in principle before incorporating. Too many landlords form limited companies only to discover their preferred properties become unmortgageable or prohibitively expensive to finance.

The company route will continue evolving as more lenders adapt their criteria and tax rules shift with political changes, making informed decisions more valuable than following the latest trend.