Overall, those aged 65 and over accounted for 16% of individuals who submitted a tax return, whereas 16 to 24-year-olds made up 2.7% of total filers.
The new data is part of an analysis by HMRC into the demographic data of self assessment taxpayers. The largest group of self assessment filers were 45 to 54-year-olds, who accounted for 24% of all tax returns submitted.
Men accounted for 62% of those who submitted a return last year, compared to 38% who were women. The data also showed that almost 146,000 people submitted their tax return at the earliest opportunity between 6 and 11 April 2021.