Saturday’s Self Assessment deadline turned out to be the busiest in the history of HMRC Online Service, with the Government’s tax return system processing a total of 980,000 Self Assessments on Friday 30th and Saturday 31st January.

Self Assessment “rush hour”, which usually occurs around 5pm on deadline day, arrived earlier than usual this year with the deadline falling at the weekend – between 11am and midday HMRC’s system processed 530 returns every minute. With concerning statistics appearing in the run-up to the deadline, HMRC also reported that around 95% of all calls to personal tax helplines on deadline day were answered.

As has become the trend, a record number of Self Assessments were completed online this year. Over 85%, or 8.76 million, returns were filed online. Overall around 210,000 more returns were filed on time this year.

The figures aren’t all positive though – the number of Self Assessments filed late – or not at all – jumped significantly this year after enjoying four years of reductions. Last year some 710,000 returns were filed late, however that figure leapt to 890,000 this January, netting HMRC an additional £18 million in late filing penalties.

Ruth Owen, HMRC’s Director General of Personal Tax said:

“This is another record-breaking year for Self Assessment, with 210,000 more people filing their returns on time than last year.

“We’re grateful to the overwhelming majority of people who sent their returns on time. If you’re one of the minority who missed the deadline, you still need to get your tax return to us as soon as possible, to avoid further penalties and interest mounting up.”

As the number of self-employed workers and employees with second jobs continues to climb, more and more people are required to file personal tax. Some 390,000 more Self Assessments were due in January 2015 than in 2014. Commentators believe HMRC is not doing enough to explain their responsibilities to these new business owners, which may explain the sudden rise in tardy filers.

Find out how to deal with missing the Self Assessment deadline here.