Mental health: The leading cause of long-term absence

As we mark Mental Health Awareness Week (11th-17th May), new figures show the scale of mental health-related absence.

Poor mental health is the leading cause of long-term sickness absence in the UK, and data from MetLife UK reveals that a staggering 17.1 million working days were lost because of it in 2025.

Nearly half (47%) of HR leaders say that poor mental health now accounts for the majority of long-term sick leave taken in their organisation.

Women accounted for the majority of lost days due to mental health – it makes up roughly 10% of all sickness days taken amongst women, and around 7% of those taken by men.

So what can organisations do to tackle mental health in their workplace?

Addressing mental health: what’s an organisation’s role?

It’s important that an employer takes an employee’s poor mental health seriously, and treats it with the same care as a physical illness.

Mental health issues amongst your employees can be hard to spot, however. They can happen suddenly following a traumatic event in an employee’s personal life, or build up gradually over time.

Looking out for early warning signs and ensuring your people managers are also educated to do the same, is a foundational step in monitoring your teams’ wellbeing.

Early warning signs of poor mental health

These might include:

More frequent absences than usual, or turning up late to work
A drop in performance, quality of work, or time it takes to complete tasks
Changes in usual behaviour, such as how they present themselves, how they communicate with others, or showing less interest than usual in tasks they’ve excelled at or enjoyed before.

People managers play a critical role in detecting these signs. Working from home makes it trickier, so having frequent one-to-one catch-ups or more formal meetings with each employee is key.

No one should expect a manager, or for that matter an organisation as a whole, to be an expert in all things mental health. But some education and training to help managers have difficult conversations, show empathy, and listen to their team members goes a long way in helping an employee feel heard and supported.

In the UK, employers have a legal ‘duty of care’, which means they must do all they reasonably can to support employees’ health, safety and wellbeing. That includes making sure the working environment is safe, carrying out risk assessments, and protecting staff from discrimination. It also means they must treat mental and physical health as equally important.

Is poor mental health considered to be a disability?

By law someone with poor mental health can be considered to be disabled if:

it has a ‘substantial adverse effect’ on their life, for example frequently struggling to focus on a task or taking longer than usual to complete tasks
it affects their ability to do their normal day-to-day activities such as sticking to a schedule or interacting with others
it lasts, or is expected to last, at least 12 months

Poor mental health can still be considered a disability even if symptoms are not present all of the time.

If an employee is classed as disabled, their employer must:

not discriminate against them because of their disability
make reasonable adjustments

Reasonable adjustments can vary, but often simple changes such as working with the employee to plan out their workload or tasks for the day, allowing them flexible start and finish times, or permitting more rest breaks, can make a big difference.

What support can an organisation offer?

Alongside reasonable adjustments and supportive conversations when needed, organisations can also offer mental health support provisions in the form of an Employee Assistance Programme (EAP). These may offer access to counselling services, GP services, and more health and wellbeing tools.

You can also foster a workplace culture where open discussion around mental health is encouraged, perhaps nominating employees who are mental health advocates or champions, and arranging quarterly workshops or activities

Managing mental health-related absence

Just like any other absence, it’s vital that absences due to mental health are managed appropriately.

If you’re not recording instances of absence amongst your teams, you’ll be missing useful data, struggling to juggle team availability, and potentially having negative impact on your employees’ engagement and satisfaction.

If you’re using spreadsheets to manage absence, or different locations or offices are using their own siloed system, then errors, inaccuracies and inconsistencies mean your records are unreliable.

Best practice requires all instances of absence to be recorded, ideally in a centralised absence management system, alongside a clear reason for each absence. This allows you to record absences over time and look back at your data to identify possible patterns or trends.

This way, you may be able to spot an individual who has taken a high number of absences in a short period of time, prompting a conversation with them and uncovering the fact that they may be struggling.

This forms part of the bigger picture, allowing HR teams and people managers to become more proactive (rather than reactive) in their efforts to prioritise employee wellbeing more effectively.