Fill in the figures, then click Work out my rental tax.
Result
The numbers
| Item | Amount |
|---|
What to do
| Step | What it means |
|---|
What it does, and what it leaves to you
- Covers: an individual's residential rental profit for 2025/26 and 2026/27, the Section 24 restriction on finance costs, the 20% credit, the personal allowance taper and the old-rules comparison.
- Gives: your tax bill, the credit, the extra tax versus full deduction, tax on the property as a share of real profit and a Self Assessment checklist.
- Not decided: Scottish bands, furnished holiday lets, company ownership, carried-forward finance costs and losses, savings and dividend income, the property income allowance, and anything that changed after this was written.
Common questions
What is Section 24?
Since April 2020 an individual landlord can no longer deduct mortgage interest and other finance costs from rental income. Instead you are taxed on the profit before finance costs and get a basic-rate (20%) tax credit on those costs.
Who does it hurt?
Higher-rate and additional-rate taxpayers, and basic-rate landlords whose rent profit pushes total income over the higher-rate threshold. A basic-rate taxpayer with income well below that threshold is usually unaffected, because the 20% credit equals the old relief.
Can I pay more tax than I actually make?
Yes. Because tax is worked out on profit before finance costs, a heavily mortgaged property can have a small real profit and a large tax bill. This calculator shows tax as a share of your real profit.
Does it apply to a limited company?
No. A company deducts mortgage interest in full as an expense. Moving properties into a company has its own tax and legal costs, so get advice before acting.
How do I claim the 20% credit?
Enter your finance costs in the finance costs box of the UK property pages of your Self Assessment return, not as an expense. The credit is then calculated for you.
Is my data uploaded anywhere?
No. Everything is calculated in your browser and nothing is sent.