HM Revenue and Customs (HMRC) is urging millions of workers across the UK to act swiftly, with a critical tax deadline now fast approaching on 31 January 2026.
The Looming Penalties for Late Filers
Individuals required to submit an online Self Assessment tax return for the 2024/25 tax year must do so, and pay any tax owed, by 11.59pm on 31 January 2026. Failure to meet this deadline triggers an immediate financial penalty. The initial fixed charge is £100, but this can escalate quickly for those who ignore the reminder.
If a return remains outstanding for three months after the deadline, daily penalties of £10 are added, potentially reaching a maximum of £900. After six months, a further penalty of 5% of the tax owed or £300 is applied, whichever is greater. A final 5% or £300 charge is added after 12 months.
Separate charges apply for late tax payments, starting with a 5% fee on the unpaid amount at 30 days late, repeating at six and twelve months. Interest will also be charged on any overdue tax.
Who Needs to Act and How to Avoid Fines
Newcomers to the Self Assessment system must ensure they have their Unique Taxpayer Reference (UTR) to file correctly. Crucially, HMRC is also reminding people who believe they no longer need to submit a return to contact them directly.
Failing to inform HMRC of a change in circumstances, such as if you have stopped being self-employed, no longer pay the High Income Child Benefit Charge, or have ceased renting out a property, could still result in a fine. The department has explicitly stated on social media: "The #SelfAssessment deadline is fast approaching. If you no longer need to submit a tax return, let us know as soon as possible."
Stopping Self-Employment Correctly
If you are stopping trading as a sole trader or leaving a business partnership, you must send a final tax return. This document should include your final trading income, profit or loss, allowable expenses, any Capital Gains Tax due, and capital allowances. Once HMRC is notified of your changed status, they will confirm in writing whether you need to continue filing returns.
However, some individuals may choose to remain registered as a sole trader to access benefits like Tax-Free Childcare or to make voluntary Class 2 National Insurance payments.
