More workers will pull "sickies" today than on any other day of the year, according to researchers.
The need to recharge batteries after the initial post-Christmas shock of being back in the office, hugely increased workloads, and dissatisfaction with holiday entitlements, are leading to more people "falling ill", according to a survey of over 4,000 employees in Britain.
But the prospect of having to wait until a bank holiday - and a reluctance to take annual leave - persuades people to skive, the study for TV channel Sky Travel revealed.
The worst offenders on National Sickie Day are Northerners, with Liverpool named as the sickie capital of Britain. Workers in the city took an average of 13 days a year off sick compared with three in London, the report said.
Work-life balance expert Professor Cary Cooper, who helped with the research, said: "Early February is a very popular time for taking a sickie. The first bank holiday still seems a long way off, the days are gloomy and many people are still feeling the post-Christmas blues."
A TUC spokesman said: "The truth is that sickness absence is going down. Employees are more likely to struggle into work when they are too ill than let colleagues down by throwing a bogus sickie.
"With February a top month for colds and flu, the worry is that people with genuine illness will now have to struggle into work and infect their colleagues to avoid suspicion of cheating."