Hundreds of thousands of taxpayers are making a last-minute dash to beat a deadline for filing their online self-assessment returns, the revenue body has reported.
Just over one million taxpayers still have to file their returns by midnight on Thursday, and those who fail to do so will automatically be fined £100.
A spokesman for HM Revenue and Customs (HMRC) said that by lunchtime a total of 9.4 million returns had been made, leaving 1.2 million still due in.
Some 445,000 people filed their returns on deadline day in 2012 and the busy pattern is being repeated this year, with 200,000 taxpayers sending their returns on Thursday morning, the revenue body said.
A persistent hardcore of people always fail to meet the deadline.
Last year 9.45 million self-assessment tax returns were filed on time, equating to nine out of 10 of these taxpayers.
The spokesman said: "If you still haven't sent in your tax return online, you've got until midnight tonight to file to avoid a £100 penalty, please also make sure to pay what you owe."
The "self-assessment rush hour" last year happened between 4pm and 5pm on January 31, when more than one return every six seconds was being received by HMRC.