The deadline to submit your self-assessment tax return and settle any tax liabilities is quickly approaching. You must file your tax return with HMRC by January 31, 2026, for the 2024/25 tax year. It is estimated that about 12 million individuals, including self-employed individuals, will need to file their taxes.
While most people have taxes automatically deducted from their salaries, those who are self-employed or have additional untaxed earnings must handle their taxes through self-assessment. There are various reasons why you might need to file a self-assessment tax return, and failure to do so on time will result in a £100 fine.
If you fail to submit your self-assessment after three months, you will face additional penalties of £10 per day, up to a maximum of £900. After six months, a further penalty of 5% of the tax owed or £300 (whichever is higher) will be imposed, with a similar penalty after 12 months of non-compliance.
Upon filing your self-assessment tax return, you will be informed of the amount of tax you owe, with the payment deadline also set for January 31. Additionally, you will likely need to make an initial payment on account for the 2025/26 tax year. Failure to pay your outstanding tax within 30 days, six months, and 12 months will incur a 5% charge, along with interest on late payments.
According to Money Helper, circumstances that may require you to complete a self-assessment form include certain criteria.