Poor mental health among British workers leads to 5m sick days and bill of billions

British workers are in the grip of a mental health crisis. As of last Tuesday, UK employees had taken 5m sick days in 2026 as a result of poor mental health, according to research by Simplyhealth.

Since the pandemic, Britons have been far more likely to take sick leave. Separate research published last year showed the number of sick days taken by British workers had almost doubled since the pandemic, from 5.8 days per employee per year in 2019 to 9.4 days in 2025, when the leading causes of short-term absences were minor illnesses such as coughs and colds, mental ill health, caring responsibilities for children and stress.

That has economic implications. A report by Deloitte, published in 2024, found that employers were losing £51bn a year to employees with poor mental health. And it wasn’t just sick days that were costing them – presenteeism, which describes people coming to work even when they’re ill and unable to perform their job to their full capacity, costs employers £24bn a year.

According to a survey of 1,775 small and medium firms by Access People HR, the steepest increases in sick leave days per company between 2019 and 2023 were in agriculture, forestry and fishing and manufacturing. Administration and, ironically, recruitment recorded decreases.

GPs aren’t helping the situation. A recent investigation by the BBC found that hundreds of GPs routinely sign patients off work for mental health issues without asking questions. Some 540 GPs said they had never refused to sign a “fit note” linked to mental health. These notes provide evidence to employers that people are too sick to work. Doctors issued almost 850,000 more fit notes in 2025 than they did in 2019, the BBC said.

It’s hard to pin down one reason workers’ mental health is suffering so badly, but we do known the current spike began around the pandemic. Alex Bailey, chief executive of the leadership consultancy Bailey & French, says people are being asked to cope with more change at work than ever before.

From company reorganisations to a new focus on AI to rounds of redundancies and the move to working from home (and back to the office again), Bailey says workers are now experiencing an average of 10 big changes at work each year. “It used to be two,” she says.

The Simplyhealth research showed that while younger workers are more likely to take time off for mental health concerns, their older colleagues tend to be off for longer.

One in 10 35- to 54-year-olds took between eight and nine days off for mental health problems including anxiety, depression, stress and burnout. One in 20 workers aged 55 or over took between nine and 11 days.

Employers are losing patience with sickness absence. The Confederation of British Industry (CBI) has raised particular concerns about fit notes. “The suggestion that some GPs sign people off without engaging with how sick they are, and whether they really are fit to work or not, is concerning, said a spokesperson. “If employers can’t trust fit notes and sick pay is due from the first day off, they’ll worry that sickness absence will surge during the World Cup later this summer.”

Public servants aren’t OK. According to research by the government’s Health and Safety Executive (HSE), last year people working in the public sector, including defence, had the worst mental health, with 3.5% reporting high levels of work-related stress, depression or anxiety. That was followed by those in health and social care, 2.8% of whom suffered from poor mental health, and education where 2.6% said they were suffering.

Fit notes replaced sick notes in 2010. The idea was that doctors would use them to provide advice to employers about how to support employees’ return to work if they had been off for more than seven days. In practice, 93% of patients are simply declared “not fit for work”.

In November Pat McFadden, the minister for work and pensions, said the government was “going to try some different ways” to shake up the fit note system. That might include having non-medical practitioners making a call on “how ill [the patient is] and how long they need to be off or whether they could in fact be better off at work”, he said.

McFadden was speaking at the launch of a pilot programme aimed at creating a certified standard which helps employers to create in-house health provision for their workers. Employers including British Airways, Currys and Ford are testing a scheme which costs between £60 and £180 per employee per year, paid for through a pooled funding model.

Hannah Strawbridge, an employment lawyer at Inspire Legal Group, says she has seen an increase in employers offering settlements to get rid of sick employees.

“If you’re paying someone sick pay and then you’re not sure if they’re coming back… some of those employers are taking a commercial decision,” she says.

Still, if you thought it was bad in the UK, spare a thought for German employers. Workers in Germany take an average of 15 days off per year, compared with just eight days across the whole of the EU.

The country suffers from the same problems as the rest of Europe: an ageing society and the effects of the pandemic causing a rise in respiratory and mental health problems, reports the Economist.

But Germany’s sick leave policy is unusually generous, giving workers full pay for six weeks per illness. Oliver Bäte, the chairman of Allianz, Europe’s largest insurer, has called the country the sick day “world champion”.

Photograph by Justin Paget/Getty Images