⚠️Renters Rights Act — 1 May 2026.See what changes →

⚠️Renters Rights Act — 1 May 2026.See what changes →

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Landlord Finance11 min read24 March 2026

Buy-to-Let Tax 2026: Income Tax, Capital Gains and the Section 24 Trap

A complete guide to buy-to-let taxation — income tax on rental profits, the mortgage interest restriction, capital gains tax rates, and how to reduce your liability legally.

Buy-to-Let Tax Has Changed Dramatically

Since 2017, buy-to-let taxation has become far more complex. The removal of mortgage interest relief (Section 24), lower CGT allowances and SDLT surcharges mean many landlords pay substantially more tax than a decade ago.

Income Tax on Rental Profits

Taxable rental profit = rental income − allowable expenses

Allowable expenses: Letting agent fees, maintenance and repairs (not improvements), insurance, ground rent and service charges, accountant fees, advertising costs.

Not allowable: Capital improvements, personal expenses, your own unpaid labour.

Section 24: The Mortgage Interest Trap

Since 2020, mortgage interest cannot be deducted from rental income. Instead you get a 20% tax credit.

Example — £15,000 rent, £10,000 mortgage interest:

  • Old system: £5,000 taxable profit → 40% tax = £2,000
  • New system: £15,000 taxable profit → 40% tax = £6,000 − £2,000 credit = £4,000 net
  • This doubles the tax bill for many higher-rate taxpayers — the main reason landlords are incorporating into limited companies.

    Limited Company Buy-to-Let

    A limited company avoids Section 24 entirely. It pays corporation tax (19–25%) and can deduct mortgage interest as a business expense.

    Pros: Full mortgage interest deduction, lower effective rate, easier succession.

    Cons: Higher mortgage rates, dividends taxed when extracted, higher accountancy costs.

    Always get specialist tax advice before incorporating.

    Capital Gains Tax on Sales

    2026 CGT rates on residential property:

  • Basic rate taxpayer: 18%
  • Higher/additional rate: 24%
  • Annual exempt amount: £3,000
  • Deductible from gain: Purchase price, SDLT on purchase, legal fees, capital improvements, estate agent fees on sale.

    SDLT Surcharge on Buy-to-Let Purchases

    An additional 3% SDLT surcharge applies to all second or subsequent residential property purchases.

    On a £300,000 buy-to-let: standard SDLT £2,500 + surcharge £9,000 = £11,500 total SDLT.

    Record-Keeping for Tax

    HMRC expects: all rent received, all expenses with receipts, capital improvement records, tenancy agreements, mileage logs.

    LetCompliance tracks monthly income and costs per property — giving you and your accountant clean data at year-end.

    Track your rental income and tax data →

    Track all this automatically with LetCompliance

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