This was a 7% increase since 2019, when the number of days lost was 139m. However, the number of days lost has fallen consistently since 1996, with the exception of the period 2020-2022.
The sickness rate in 2024 was 2% and has remained relatively consistent since 2019.
Although the number of days lost to sickness has fallen since 2022, it is still crucial for HR leaders to foster an open culture where employees feel comfortable discussing their sickness and seeking support, explained Charlotte Neal, head of community connections at employee benefits provider Reward Gateway.
She told HR magazine: “The best organisations foster safe cultures where health is openly discussed, and managers are properly equipped to signpost to holistic and flexible wellbeing benefits that cater to all of life’s health needs, not just the ‘trendy’ conditions.
“Whether this is chronic, postpartum or seasonal, it’s crucial that employees know where to go when they are experiencing sickness. Starting these conversations doesn't need to be difficult. Awareness days are a great way to start, branching out into talks, first-hand accounts and expert analysis where relevant and possible.”
Read more: Majority of UK employees unable to take sick days
The ONS’ sickness absence data also shows that the average number of days lost to sickness per employee was 4.4 last year. This was a 19% increase since 2020, when the average number of days was 3.7.
However, the average number of sickness days lost last year decreased by 21% since 2022.
In-house research conducted by representatives of the staff leave software firm Timetastic, found that the average number of sick days taken by baby boomers (people born between 1946 and 1964) in 2024 was 4.0 compared with 2.7 days taken on average by Gen Z (people born between 1997 and 2012) in 2024.
The number of sick days baby boomers took off from work increased 53% between 2020 and 2024. This is compared to a 22% increase in sick days taken by Gen Z between 2020 and 2024.
Senior leaders should lead by example, stated Brett Hill, head of health and protection for the consultancy Broadstone.
Speaking to HR magazine, he said: “Senior leaders need to be open, where appropriate, about their own human experiences, rather than reinforcing outdated stereotypes about the need for leaders to be ‘indestructible’ and ‘infallible’. This helps to normalise open, honest conversations about health, especially emotional health.
“At the same time, employers need to equip line managers to have health-related conversations appropriately and with confidence. This means providing training and encouraging use of line manager support services offered by some benefit providers, so that managers feel capable and well supported in handling sensitive issues. Employers should also ensure that they have clearly communicated and consistently applied policies for reporting, recording, and managing sickness absence. This gives employees confidence they’ll be treated fairly, while also helping line managers feel supported in applying policies consistently."
Read more: Is Sunak right about "sick-note culture"?
Supporting employees who are returning from sick leave is just as important as encouraging conversations around health at work, Hill added.
He said: “HR leaders can start by setting out an appropriately phased return to work plan, with clear milestones and regular check-ins. Being flexible and making reasonable adjustments is far more preferable to an employee feeling overwhelmed and needing further time off.
“It’s also important to ensure that line managers are supported, especially those with less experience. Even a well-designed return to work plan can fail if a manager lacks the experience, bandwidth or support to carry it through effectively.”
Timetastic analysed anonymised sick leave records logged through the platform used by over 8,000 businesses across the UK, representing more than 200,000 users. They analysed data from 2012 to early 2025.
