Landlord Limited Company Tax Calculator — Personal vs Company (2026/27)

What this calculator settles — and what it cannot

It answers the annual question honestly: on your income, your mortgage and your plan for the profits, which structure pays less tax each year — and if you already own the property, how many years of that saving the one-off transfer cost would eat. It cannot tell you about lender terms, inheritance planning or whether HMRC would accept incorporation relief on your portfolio; those are the adviser conversation this calculator is meant to make shorter and cheaper.

How the personal route is computed

• Rental profit (rent minus expenses, not minus interest) is stacked on your other income and taxed at your marginal band — 20% / 40% / 45% now, 22% / 42% / 47% on the 2027/28 preview.
• Mortgage interest earns a 20% credit (22% from 2027), capped at the lowest of finance costs, property profit and your income above the personal allowance — the cap is what surprises retired and low-income landlords.

How the company route is computed

• Interest is deducted in full. Profit after interest pays Corporation Tax at 19% up to £50,000, 25% above £250,000, with marginal relief between.
• If you draw the profit as dividends, dividend tax applies on top: £500 allowance, then 10.75% / 35.75% / 39.35% depending on where the dividends land above your other income. These rates rose in April 2026 — the quiet reason the company answer is less clear-cut than 2025 blogs suggest.
• Retaining profit avoids the second layer entirely — the company route wins most clearly for landlords reinvesting rather than living on the rent.

The transfer estimate

Moving a property you already own into a company is a disposal at market value. The estimate charges CGT on the gain after the £3,000 exempt amount at 18%/24% by your band, and SDLT on the full value at the standard bands plus the 5% additional-dwelling surcharge. Incorporation relief (a genuine, actively managed business) can defer the CGT; nothing routinely removes the stamp duty. Payback years = one-off cost ÷ annual saving. Ten years or more usually means: buy the next one in a company, leave this one alone.

What is missing on purpose

Company accountancy costs (£1,000+ a year), the mortgage-rate premium on company buy-to-let lending, ATED for properties over £500,000, the personal allowance taper above £100,000 on the company side (your other income still decides it), Scottish rates (personal route uses UK bands here), and any CGT on eventually selling through the company. All of them nudge the answer; none changes the shape of it. Read the full guide before deciding.