About CalculateMyTax

What the site is for

Most landlords want to know two things: how much tax their rent adds, and why. The rental income tax calculator answers the first question using your own figures. Our guides answer the second, explaining the rules HMRC applies in plain English, from allowable expenses for landlords to Section 24 mortgage interest relief.

How we keep the figures accurate

Every rate, band and allowance the site uses lives in one rates file. The calculator, the rate tables and the guides all read from that same file, so a guide cannot show one figure while the calculator uses another. A change made in the rates file carries through to every page that uses it.

We check the rates against GOV.UK, HMRC and gov.scot. They were last verified on 13 September 2026, and each rate table on the site shows the date it was checked.

The worked examples in our guides are not typed in by hand. They are produced by the same calculation engine that runs the calculator, so every example follows exactly the same rules as the figures you work out for yourself.

What the calculator covers

• The tax years in our rates file, including the separate property income rates from 6 April 2027.
• England, Wales and Northern Ireland, and Scotland's own tax bands.
• Section 24 mortgage interest relief with all three limits, and interest carried forward.
• Allowable expenses, the property allowance and Rent a Room relief, with the cheapest route recommended.
• Joint owners at any split, several properties, and losses brought forward.
• Whether Making Tax Digital for Income Tax applies to your rental income.

Where it stops

The calculator does not cover property owned through a limited company, landlords who live abroad, overseas property, Capital Gains Tax, savings and dividend income, pension contributions or Gift Aid. For tax years that have not started yet, some figures may be assumed where Scottish or Welsh rates have not been set. The disclaimer on estimates and tax advice sets out these limits in full.

Free and independent

The calculator and guides are free to use, and you do not need to sign up. There are no adverts, no affiliate links and no tracking. We set no cookies and use no analytics.

The calculator runs in your browser, so the figures you type into it are not sent to us or stored by the site. Our privacy policy and cookie policy explain this in more detail.

Estimates, not advice

Results are estimates based on the figures you enter and the published rates. They are not tax advice and cannot take account of everything in your circumstances. Before you file a tax return or make a financial decision, check your position with HMRC or a qualified tax adviser.