London, 07 May 2026: A Freedom of Information request submitted to HMRC has revealed that self-employed workers on the lowest incomes are significantly more likely to miss the Self Assessment filing deadline than higher earners. Those below the basic rate tax threshold are filing late at nearly double the rate of higher and additional rate taxpayers.
The data, covering tax years 2019/20 to 2023/24, shows that in the most recent year (2023/24), 5.9% of below basic rate tax self-employed filers submitted their return after the 31 January deadline, compared with 3.1% of basic rate taxpayers, 2.7% of higher rate taxpayers and 2.6% of those paying additional rate tax. The pattern holds consistently across all years in the dataset, including the years 2019/20 and 2020/21, when HMRC waived the penalty for late filing if submitted before 28 February.
In total, around 180,000 self-employed individuals filed late in 2023/24, a figure that has fallen steadily in recent years, though the gap between the lowest earners and everyone else shows little sign of closing. Of these, 94% were either below basic or basic rate taxpayers.
The findings point towards a potential knowledge gap among lower earners regarding how and why filing a tax return is done, as well as broader structural issues. Lower earning self-employed workers are more likely to manage their tax affairs independently, without access to accountants or financial advisers, and may be more exposed to the income volatility that makes fixed financial deadlines harder to meet. The fact that this disparity is consistent across five years of data suggests it is systemic.
For self-employed workers, the Self Assessment tax return is a key milestone when income, tax and savings decisions are all in view at once, but separate research from PensionBee shows that nearly three in four self-employed people without a pension aren’t aware that contributions receive tax relief. Eligible employees benefit from auto-enrolment, which removes some of the need for pro-active engagement towards pensions. For the self-employed however, no such default arrangement exists, and if the lowest earners are finding the Self Assessment filing process the most burdensome, they are also the least likely to be building retirement security alongside it, and are therefore most at risk.
Lisa Picardo, Chief Business Officer UK at PensionBee, said: “Late filing of Self-Assessment tax returns is not evenly spread across the self employed population. It’s heavily concentrated among those on lower incomes, many of whom sit within what we describe as the ‘invisible workforce’.
“For many of these workers, unpredictable income and limited support make it genuinely harder to stay on top of financial administration and obligations, whether that is filing a tax return or saving into a personal pension. Missing the deadline is often a symptom of a wider pressure that the system does not adequately account for.
“It also highlights a broader risk. Those with earnings below the basic rate threshold are the group that Auto-Enrolment was never designed to reach. They are managing their finances alone, often without additional support or safety nets to fall back on. If we are serious about supporting the smallest businesses, closing this administrative gap has to be part of the conversation.”
%201.png){kind=small}