About the free Section 24 Calculator (Lite)

Section 24 changed how mortgage interest is treated for landlords who own property in their own name. Mortgage interest is no longer taken off rental profit. Instead you get a tax credit at the basic rate: 20%, rising to 22% from 6 April 2027 in England, Wales and Northern Ireland.

This free calculator shows how that changes the tax on one rental property for 2025/26, 2026/27 and 2027/28, with UK and Scottish income tax bands.

Worked example (higher-rate taxpayer, 2026/27)

Yearly rent£12,000
Other allowable costs£2,000
Mortgage interest£6,000
Tax on £10,000 profit at 40%£4,000
Less 20% credit on £6,000 interest−£1,200
Tax due on the property£2,800

Next step

Rental Income & Section 24 Tax Calculator

Work out the tax on a whole portfolio, with Section 24, the 2027 rates and the personal allowance, year by year.

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Section 24 questions

What is Section 24 for landlords?

The rule that stops individual landlords deducting mortgage interest from rental profit. Instead, a tax credit equal to 20% of the interest is taken off the tax bill. It affects property owned in your own name, not through a limited company.

Does Section 24 affect basic-rate taxpayers?

Often only a little, because the credit matches the basic rate. It can still push some landlords into a higher band, because rental profit is now counted before mortgage interest.

What changes for Section 24 in April 2027?

From 6 April 2027 property income is taxed at 22%, 42% and 47% in England, Wales and Northern Ireland, and the mortgage interest credit rises to 22% to match.

Does Section 24 apply to limited companies?

No. Companies deduct mortgage interest as a business cost and pay Corporation Tax on their profit. Whether a company suits a landlord depends on their wider situation, so many speak to an accountant.

Education, not advice. Rules change and depend on your circumstances. Check GOV.UK and speak to a qualified adviser before you act.