According to HM Revenue and Customs, around a million people have missed the deadline to submit their self-assessment tax returns and face automatic penalties.
HMRC said 27,456 taxpayers filed their returns in the last hour before the midnight deadline on Saturday, after the tax agency kept helplines open over the weekend and expanded web chat services to help late filers.
The busiest time for online submissions was between 5pm and 6pm on Saturday. A total of 475,722 people filed on the final day, bringing the total number of filings for the 2024-25 tax year to around 11.5 million.
Anyone who fails to submit their tax return on time will now face an automatic £100 penalty, even if there is no tax to pay or the tax owed has already been paid.
Myrtle Lloyd, HMRC’s chief customer officer, said: “Thank you to the millions of people and agents who submitted their self-assessment tax return and paid all the tax owed by January 31. Anyone who missed the deadline should submit their tax return as soon as possible as penalties and late payment interest may apply.”
While most workers automatically pay tax via PAYE, self-assessment remains compulsory for those on additional income. This includes people who earn more than £1,000 in the tax year through self-employment or from renting out property or land.
Some people were no longer required to file a tax return this year, including those whose only previous reason for filing was to earn more than £150,000 or parents who now pay high income child benefit through PAYE rather than self-assessment.
A similar number of taxpayers missed the deadline last year. HMRC’s penalty system increases the longer a return is outstanding. In addition to the initial £100 fine, latecomers can face a daily fine of £10 after three months, capped at £900, followed by further penalties at six and 12 months.
Separate penalties apply for late tax payments, with a 5% surcharge and interest on unpaid amounts being applied after 30 days, six months and 12 months.
HMRC said it would consider reasonable excuses for missing the deadline and remove penalties if necessary. However, tax experts warn against delaying action.
Charlene Young, senior pensions and savings expert at AJ Bell, said: “Even if you intend to appeal a penalty, it often makes sense to pay it upfront to avoid adding interest if the appeal fails. If you owe tax and can’t pay in full, a payment plan may be available to you – but ignoring the problem will only make it worse.”
