Is mental health a legal duty? What UK employers actually have to do

Ask most UK business owners whether they have a legal duty to protect their employees’ mental health, and you’ll often get a hesitant answer. Physical safety feels clear-cut: guard the machinery, test the wiring, keep the fire exits clear. Mental health can feel like a “nice to have” — a wellbeing perk rather than a legal obligation.

It isn’t. Under UK law, an employer’s duty to protect the health of employees explicitly includes their mental health — and the Health and Safety Executive (HSE) expects work-related stress to be assessed and managed just like any other workplace risk. In 2024/25, an estimated 964,000 workers in Great Britain were suffering from work-related stress, depression or anxiety — around half of all work-related ill health, and behind roughly 22.1 million lost working days. It is now the single biggest cause of work-related ill health in the country.

So where exactly does the legal duty sit, and what do you actually have to do about it? Here’s the plain-English version.

The short answer: yes — and it’s not new

There is no single “Mental Health Act” for the workplace. Instead, the duty is woven through three pieces of existing legislation that most UK employers already know for other reasons. Mental health simply sits inside them.

Where the duty comes from

The Health and Safety at Work etc. Act 1974

The foundation of UK workplace safety law. Section 2 of the Health and Safety at Work etc. Act 1974 requires every employer to ensure, so far as is reasonably practicable, the health, safety and welfare of employees. “Health” here covers both physical and mental health — the HSE is explicit that psychological wellbeing falls within this general duty.

The Management of Health and Safety at Work Regulations 1999

The Management of Health and Safety at Work Regulations 1999 require a “suitable and sufficient” risk assessment of the risks employees face at work, and the HSE has confirmed this includes the risk of work-related stress. In practical terms: if stress is a foreseeable risk in your business — and in most workplaces it is — you are expected to assess it and take reasonable steps to reduce it.

The Equality Act 2010

A mental health condition can meet the legal definition of a disability under the Equality Act 2010 if it has a substantial, long-term effect on someone’s ability to carry out normal day-to-day activities. Where it does, the employee is protected from discrimination and you have a duty to make reasonable adjustments — enforced through employment tribunals, a separate route from HSE enforcement but one that carries real financial and reputational risk.

The HSE Management Standards: your practical framework

If the legislation tells you that you must manage work-related stress, the HSE Management Standards tell you how. They set out six areas of work that, poorly managed, are the most common causes of stress — and they double as the clearest checklist for what a stress risk assessment should cover: demands (workload and working environment), control (how much say people have over their work), support (encouragement and resources from managers and the organisation), relationships (positive working and tackling unacceptable behaviour), role (whether people understand their role and avoid conflicting demands) and change (how organisational change is managed and communicated).

What you actually have to do

The reassuring news is that meeting the duty is largely about being systematic. In practice, a compliant employer should be able to show that they carry out a stress risk assessment across the six Management Standards areas and review it when things change; act on what it finds, rather than filing it away unread; give line managers the mental health training to spot the early signs of stress and hold supportive conversations, since managers are usually the first line of defence; provide accessible support such as Mental Health First Aiders or an employee assistance programme; make reasonable adjustments for employees whose condition meets the Equality Act threshold; and keep records of assessments, actions and training — the evidence that shows the duty was taken seriously.

Why getting this right matters

Beyond the legal exposure, the business case is hard to ignore. Work-related stress, depression and anxiety accounted for around 22.1 million lost working days in 2024/25 — an average of nearly 23 days for every affected worker. Those costs land as absence, lost productivity, recruitment to replace people who burn out and, at the sharp end, tribunal claims and HSE enforcement. Rates are highest in sectors such as public administration and defence, human health and social work, and education, but no workplace is immune — and managerial roles carry particular risk from high emotional demands and heavy workloads.

Frequently asked questions

Is mental health really covered by health and safety law?

Yes. The Health and Safety at Work etc. Act 1974 and the Management of Health and Safety at Work Regulations 1999 both apply to psychological health, not just physical safety. The HSE treats work-related stress as a risk employers must assess and manage.

Do we legally have to carry out a stress risk assessment?

If work-related stress is a foreseeable risk in your organisation — and in most it is — then yes. The Management Regulations require you to assess significant risks to health, and the HSE’s Management Standards set out how to do it.

Is a mental health condition classed as a disability?

It can be. Under the Equality Act 2010, a condition counts as a disability where it has a substantial, long-term effect on normal day-to-day activities. Where it does, you must make reasonable adjustments and protect the employee from discrimination.

Do we have to provide Mental Health First Aiders?

There is no specific legal requirement to appoint Mental Health First Aiders, but providing trained support — backed by proper mental health training — is one of the clearest ways to show you are meeting your wider duty to manage work-related stress and support employee wellbeing.

Bring your mental health compliance under one roof

If you’re not sure your organisation could show it takes mental health as seriously as physical safety, we can help. Office Test supports UK businesses with stress risk assessments, wellbeing and Mental Health First Aid training, and practical manager guidance — all as part of a single, joined-up approach to health and safety compliance. For more on how we can help with mental health, visit our mental health training page — and do get in touch if you’d like to talk it through.

This article is general guidance, not legal advice. For obligations specific to your organisation, seek professional advice.