If you became self-employed, started renting property, or earned extra untaxed income during the 2024/25 tax year, you must register for self assessment by 5 October 2025. This applies to sole traders, landlords, gig workers, online sellers, crypto investors and others with additional income.

Registering ensures you receive a Unique Taxpayer Reference (UTR), essential to filing your return. Missing the deadline is not the end, but it can lead to penalties for late notification. HMRC has said it will consider genuine reasons for late registration, and penalties can be appealed.

If you fail to register by 5 October, you may need to file a paper return by 31 October 2025. Online returns and payments are due by 31 January 2026.

You may need to register if:

• you earned more than £1,000 as a sole trader,
• you received rental or dividend income,
• you made capital gains or cryptoasset profits,
• you earned over £10,000 in savings interest,
• you or your partner earned over £60,000 while claiming child benefit,
• or you need to pay voluntary Class 2 NICs.

Use HMRC’s online tool if you are unsure whether you need to file.

Looking ahead, Making Tax Digital (MTD) for Income Tax will apply from 6 April 2026 to sole traders and landlords with income above £50,000. Quarterly digital reporting will become mandatory, so HMRC is urging eligible taxpayers to join its pilot scheme.

Get in touch to discuss your finances.