Despite being warned about a £100 late filing penalty, it appears that some people still forgot to circle 31 January in their diary with red pen.
According to statistics released today from the Institute of Chartered Accountants in England and Wales (ICAEW), 870,000 people missed the 31 January 2016 deadline for filing their tax return online.
The automatic £100 late filing penalties means that HM Revenue & Customs (HMRC) will have been able to issue IOUs worth £87m, although those with a reasonable excuse can apply to have the fee waived (but, please note, "the dog ate my paperwork" will not get you off the hook).
Figures previously released by HMRC show those who missed the deadline are more likely to be in London than anywhere else in the UK.
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Still, it would appear people's memories are becoming better. This year, 10.4m tax returns were filed by 31 January, which is 150,000 more than last year.
"Although over 10m people filed their tax returns and over nine million of them filed online, a large number of people still missed the deadline," said Anita Monteith, tax manager at ICAEW. "Their immediate fines earned HMRC £87m, which is the equivalent of 290,000 iPads, or 73.1m packets of HobNobs."
Should those late tax returns still be outstanding after Saturday 30 April then further penalties of £10 per day will apply for each additional day they are outstanding.
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Monteith added: "Additional fines could reach up to £900, leaving people with a total bill of £1,000 by the end of July. What’s more, anyone who hasn’t filed after six months may face a further penalty of 5 per cent of the tax due or £300 – whichever is greater. The costs could rocket."
However, at least those who filed late are in good company. When Labour leader Jeremy Corbyn revealed his tax return earlier this month, he also revealed his lack of time keeping, as the date on the document read 6 February 2016, around a week after it should have been submitted to the taxman.