How to use the Section 24 Calculator (Lite): full video tutorial
See how the mortgage interest restriction changes the tax on one rental property, for 2025/26 to 2027/28. Free and educational.
▶ Play the tutorial (6:55)About this tutorial
See how much extra tax Section 24 adds on a rental compared with full mortgage interest relief. This full guide walks you through every box and result in the Property Clues Section 24 Calculator (Lite), using a worked example: £11,400 of rent, £2,200 of costs and £7,100 of mortgage interest for a higher-rate taxpayer.
What you'll learn
- Rent, allowable costs and mortgage interest under Section 24
- The extra tax compared with the old rules
- Tax due, cashflow after tax and the effective tax rate
- How the 20% credit works, and the 2027/28 change to 42% and 22%
- Questions to take to an accountant
Chapters
- £1,420 of extra tax from Section 24 (example)
- Finding your way around
- Your figures
- What counts as a cost
- The four results
- Section 24 against the old rules
- What if the interest goes up?
- What if the rent goes up?
- Why your tax rate matters
- Scottish landlords
- Looking ahead to 2027/28
- Three common mistakes
- Where the rent goes
- At a glance and recap
Figures in the video are a worked example. Property Clues tools are educational calculators and checklists, not financial, tax, mortgage or legal advice. Speak to a qualified adviser about your own situation. The voice in the video is AI-generated.