Slight drop in absences in December, attention to mental health still sorely needed

Slight decline due to Christmas period

In December, there were 53 sick days reported per 1,000 employees, compared to 63 in November. This puts the number of sick day reports almost on par with December 2024 (52 per 1,000). The absenteeism rate of 4.9% is also comparable to that of a year earlier, and therefore typical for this time of year. ‘The holiday period around the festive season causes a temporary decrease in sick leave reports, as a large proportion of the Dutch workforce is off work. This is a pattern we see every year,’ said Iris Homeijer, Director of Medical Affairs and Occupational Physician at HumanCapitalCare. 

No spike expected on Blue Monday

After the decline in December, we normally see the number of sick day reports rise again in January. Last year, that increase was sharp: the number of sick day reports in January 2025 was 63% higher than in December 2024. Despite Blue Monday's reputation as the ‘bleakest day of the year’, there was no notable spike in sick leave reports last year on this day. In 2025, Blue Monday did end up being in the top four days with the most absenteeism reports, but it was not in first place – that went to Monday 27 January 2025, a week later. It is not surprising that Mondays often top the list: reports from the weekend are usually submitted on Mondays. Starting on Valentine’s Day, the number of sick leave reports dropped noticeably again last year.

Year-round focus on mental well-being

‘Although Blue Monday is a good reason to reflect on the importance of mental health, this should not be limited to just one day,’ says Homeijer. Stress-related absences have been on the rise for years and accounts for a large proportion of the total absenteeism: 1 in 4 sick leave reports is stress-related. ‘Many of these absences are actually preventable. Prevention starts with early identification and open communication. Employers who structurally invest in a healthy work culture and resilient employees, talking to employees regularly about how things are going, significantly reduce the likelihood of long-term absenteeism.’

The winter blues affect energy, motivation and productivity

Although Blue Monday has never been scientifically proven, the effect of darker days with less daylight can certainly be felt in the winter. This can disrupt your biorhythm and lead to a sense of gloominess or fatigue. ‘This phenomenon, often referred to as the winter blues, does not necessarily lead to more sick day reports, but it can cause a decline in energy, motivation and productivity,’ says Homeijer. ‘Employers can help by stimulating connection, encouraging exercise and maintaining communication with each other. Small actions such as a walk during lunch and a sincere check-in can make a difference. Working together on vitality starts with these small steps.’