Buy-to-Let Portfolio Tax — Personal Income vs Limited Company in 2026

The Tax Landscape for Portfolio Landlords in 2026

The way buy-to-let rental income is taxed in the UK has changed fundamentally over the past decade. Understanding the current rules — and how they apply differently to personal landlords versus limited company landlords — is essential for anyone building or managing a portfolio in 2026.

Section 24 — The Rule That Changed Everything

Section 24 of the Finance Act 2015 (fully phased in from April 2020) removed the ability for individual landlords to deduct mortgage interest as a business expense when calculating taxable profit. Instead, personal landlords receive only a 20% basic-rate tax credit on mortgage finance costs.

For a basic-rate (20%) taxpayer, this is broadly tax-neutral. For a higher-rate (40%) or additional-rate (45%) taxpayer, the impact is substantial. A landlord with significant mortgage debt may find themselves paying tax on revenue rather than profit — meaning they can be technically profitable before tax but making a cash loss after it.

**Example (personal name, higher-rate taxpayer):**

• Annual rental income: £18,000
• Annual mortgage interest: £10,000
• Taxable profit before Section 24: £8,000 (old rules)
• Taxable profit under Section 24: £18,000 (mortgage interest no longer deductible)
• Tax at 40%: £7,200
• Less 20% credit on mortgage interest (£10,000 × 20%): −£2,000
• Net tax liability: £5,200 (vs £3,200 under old rules)

Limited Company Advantages for Portfolios

A limited company (typically a Special Purpose Vehicle or SPV) is taxed under Corporation Tax rules, not Income Tax. Mortgage interest remains fully deductible as a business expense. In 2026, Corporation Tax on profits up to £50,000 is 19% (the small profits rate), rising to 25% on profits above £250,000.

This means a limited company landlord on the same numbers as above would pay Corporation Tax only on the £8,000 net profit, not on the gross rental income.

Additionally, profits retained within the company are not subject to personal tax until they are extracted as salary or dividends. For landlords focused on portfolio growth rather than income drawdown, this creates a significant compounding advantage.

The Costs and Complications of Limited Company Ownership

Incorporation is not without cost or complexity:

• **Mortgage rates** — buy-to-let mortgages for limited companies typically carry higher interest rates than personal mortgages, though the gap has narrowed in 2026
• **Stamp Duty** — transferring existing personally-held properties into a company is treated as a disposal, triggering potential CGT and Stamp Duty Land Tax (including the 5% additional dwelling surcharge)
• **Accountancy costs** — company accounts, Corporation Tax returns, and payroll all cost more to administer
• **Director's loan complications** — extracting money from the company requires care to avoid unexpected tax charges
• **Mortgage availability** — while the limited company BTL market has grown, it remains smaller than the personal market

Who Benefits Most from Incorporation?

The general consensus among property tax advisers in 2026 is that limited company structures offer the clearest advantage for:

• Higher-rate or additional-rate taxpayers
• Landlords building a portfolio for long-term retention rather than near-term income
• Those with three or more mortgaged properties where the Section 24 impact is meaningful
• Landlords whose partners are not taxpayers, allowing tax-efficient dividend distribution

For basic-rate taxpayers with one or two properties and modest mortgage debt, the additional complexity and cost of a limited company may outweigh the tax benefits.

Use our [Portfolio Yield Calculator](/portfolio-yield-calculator) to model your net returns under different tax assumptions, and always take advice from a property-specialist accountant before making structural decisions.