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When to Report Additional Income to HMRC: 2025/26 Rules for Online Sellers and Renters

The 2025/26 tax year runs 6 April 2025 to 5 April 2026. When additional income from online selling or renting out part of your home means telling HMRC, per gov.uk.

·2 min read·By UK Calculator Editorial Team·Updated 17 Jul 2026

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What the source announced

The 2025 to 2026 UK tax year runs from 6 April 2025 to 5 April 2026. Gov.uk provides an online tool that checks whether a Self Assessment tax return is required for income falling within this period (gov.uk, Self Assessment).

Taxpayers with income beyond their primary source should check whether they need to tell HMRC. Gov.uk identifies selling things online and renting out part of your home as examples of additional income that may trigger this reporting check (gov.uk, Self Assessment).

The gov.uk guidance frames the additional income obligation conditionally, 'check if you need to tell HMRC', rather than as a blanket requirement. Selling things online and renting out part of your home are the two examples the guidance provides (gov.uk, Self Assessment).

What this means for your income tax

The 2025 to 2026 tax year runs from 6 April 2025 to 5 April 2026. A rental receipt or completed online sale occurring before 5 April 2026 sits within the 2025/26 return; the same type of income received from 6 April 2026 falls into the following tax year.

The gov.uk guidance directs those with additional income, such as selling things online or renting out part of a home, to check if they need to tell HMRC. The check gov.uk advises is the step that establishes whether the obligation applies to a given taxpayer's position.

Use the income tax calculator → to see how income from online selling or property rental sits alongside other earnings when working out your total income tax position for the year.

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