While most were topping up their glasses ready for a midnight toast, 160 Britons spent the hour after 11pm on New Year's Eve filing their tax return, according to HMRC.
The Revenue said that 58 more taxpayers filed their return between 11pm and midnight on New Year's Eve this year than did so the same time in 2011.
A further 27,161 Britons filed returns during the rest of the day on New Year's Eve, while 12,077 spent the first day of 2013 logged on to HMRC's website to do the same – a 35 per cent rise on the equivalent time last year.
A further 1,548 people decided to take time out from the turkey and mince pies on Christmas Day to file their tax return online – a 40 per cent increase on Christmas Day 2011, when 1,100 people did the same.
The taxman has just launched a new advertising campaign promising "inner peace" to the 10.6 million people in self-assessment who need to file a tax return. The deadline for those doing so online for the 2011-2012 tax year is 31 January.
The Revenue added: "HMRC found that people often felt a real sense of relief, or peace of mind, once they sent in their return – like a weight being lifted from their shoulders. A new ad campaign encourages people who still haven't sent their return to "do it today, pay what you owe and take a load off your mind", so they can experience "inner peace".