Landlord Tax in 2026: What Every UK Landlord Needs to Know

Understanding landlord tax in 2026 is no longer optional admin — it is the difference between a portfolio that quietly compounds and one that drains cash every month. The rules that govern how rental income is taxed have tightened steadily since the mid-2010s, and several of those changes have now fully bedded in. If you let property in the UK, this guide walks through the levers that matter most this tax year: how Section 24 mortgage interest relief works in practice, what Making Tax Digital means for your record-keeping, and the allowances that still work in your favour.

Section 24: why your mortgage is no longer a simple deduction

The single biggest shift for individual landlords remains Section 24 mortgage interest relief, fully in force since 2020. Before it, landlords could deduct mortgage interest from rental income before calculating tax. Now you cannot. Instead, you pay income tax on your full rental income and receive a separate tax credit worth 20% of your finance costs — interest on buy-to-let mortgages, and certain fees.

For a basic-rate taxpayer the effect is broadly neutral. For higher and additional-rate taxpayers it is not. Because your full rent is added to your income first, leveraged landlords can be pushed into a higher tax band, then only credited back at 20%. The result is that some highly geared portfolios are taxed on profit they never actually keep.

A worked example

Imagine a landlord receiving £20,000 in annual rent with £9,000 of mortgage interest, and assume a 40% rate only as an illustration of how a 20% finance-cost credit interacts with a higher rate. Under the old deduction they would have been taxed on £11,000 of profit. On these assumed numbers they are taxed on the full £20,000 at 40% (£8,000), then receive a 20% credit on the £9,000 interest (£1,800), leaving a £6,200 bill, compared with £4,400 if the interest had still been deducted before a 40% charge. This is arithmetic on an assumed rate. It is not a statement of the income-tax or property-income rates that apply after the Autumn 2026 Budget. This article does not state those rates, because they were not verified on an HMRC or GOV.UK page for this review. Check HMRC before you rely on any percentage.

“Section 24 does not punish profit — it punishes leverage. The more of your return that comes from a mortgaged deposit rather than equity, the harder the maths bites.”

Should you incorporate?

Section 24 does not apply to companies, so limited-company landlords can still deduct mortgage interest as a business expense and pay corporation tax on the remainder. That is why so many new buy-to-let purchases now complete inside a limited company. But incorporation is not a free win — extracting profit as dividends triggers a second layer of tax, mortgage rates for company borrowers are typically higher, and moving existing personally-held property into a company can crystallise capital gains tax and stamp duty.

• Company structures suit higher-rate taxpayers building a portfolio over the long term and reinvesting profit.
• Personal ownership often still wins for basic-rate taxpayers, or those holding one or two unmortgaged properties.
• Transferring existing property into a company is a sale in HMRC's eyes — model the CGT and SDLT before you move.
• Always take advice from a qualified accountant before incorporating; the right answer is genuinely individual.

Making Tax Digital is coming for landlords

Making Tax Digital (MTD) for Income Tax is being phased in for landlords and the self-employed. Landlords above the threshold HMRC publishes need digital records and quarterly updates. This article does not state the income threshold or the mandatory start date, because those figures were not re-checked against HMRC for this review. Read the current HMRC guidance before you plan around a date.

The practical takeaway is simple: move your bookkeeping into proper software now, while it is voluntary, rather than scrambling when it becomes mandatory. Clean, digital records also make it far easier to claim every allowable expense — which is where most landlords leave money on the table.

The allowances and deductions still working for you

Plenty of legitimate deductions survive Section 24. You can still offset day-to-day running costs against rental income before tax:

• Letting agent and property management fees
• Repairs and maintenance (but not improvements, which are capital)
• Landlord insurance, ground rent and service charges
• Accountancy fees and the cost of advertising for tenants
• Replacement of domestic items relief for like-for-like furnishings

On the capital side, remember that selling a buy-to-let triggers capital gains tax, and the annual CGT exempt amount has been cut sharply in recent years — so disposals need planning. Spreading sales across tax years, using both spouses' allowances, and timing completion carefully can all reduce the bill.

Know your real yield before you buy

Tax changes everything about what a property actually earns. A headline 6% gross yield can shrink to something far less appealing once Section 24, management fees and maintenance are stripped out. Before you commit to a purchase — or decide whether to keep an existing let — run the numbers on a net basis.

The bottom line for 2026

Landlord tax rewards people who plan. Get the ownership structure checked for your own tax position, move records into software your accountant is happy with, claim allowable expenses you can evidence, and judge a deal on net yield rather than the gross headline. This is general information, not tax advice. A property-specialist accountant should check any decision to incorporate or to sell.