Managing Workplace Stress: An Employer’s Guide

Work-related stress, depression and anxiety is now the single largest cause of work-related ill health in Great Britain. HSE’s 2024/25 figures show an estimated 964,000 workers affected, a record high, responsible for 22.1 million lost working days, 62% of all days lost to work-related ill health.

Managing stress is a legal duty, not just good practice. Employers must assess and manage the risk under the Health and Safety at Work Act 1974, and Walker v Northumberland County Council established that an employer can be personally liable in negligence for psychiatric injury caused by an unmanaged, foreseeable workload.

HSE’s Management Standards identify six areas that drive most workplace stress, and one of them, relationships, is where unresolved conflict does the most damage. Treating stress prevention and conflict resolution as two separate problems is one of the more common, and costly, mistakes employers make.

Workplace stress has moved from a soft HR concern to the leading cause of work-related ill health in Britain, and the legal, financial and human cost of getting it wrong keeps rising. This guide sets out what the law actually requires, the framework HSE expects employers to use, and the practical, everyday actions that separate a stress policy that exists on paper from one that actually reduces harm.

The scale of the problem

The trend is moving in the wrong direction. HSE’s latest annual statistics recorded 964,000 workers suffering from work-related stress, depression or anxiety in 2024/25, up from 776,000 the year before, with 409,000 of those being new cases. Stress, depression and anxiety now account for 52% of all work-related ill health, ahead of musculoskeletal disorders, and for 22.1 million of the 40.1 million working days lost to work-related ill health and injury combined. Public administration, education, and human health and social care consistently show higher than average rates.

The pattern shows up in tribunal data too. Acas figures show disability discrimination claims have risen by 30% over the past two years and now make up around a quarter of all tribunal claims, a shift driven in large part by the reclassification of mental health conditions as a disability, as CMP has written about before. Stress that goes unmanaged rarely stays a wellbeing issue. It tends to surface later as sickness absence, grievance, or a tribunal claim.

What the law actually requires

This is general information, not legal advice, and organisations should take their own legal counsel on specific cases.

Under the Health and Safety at Work Act 1974, employers have a general duty to ensure, so far as reasonably practicable, the health, safety and welfare of their employees, a duty that covers psychological harm as much as physical injury. The Management of Health and Safety at Work Regulations 1999 go further, requiring a suitable and sufficient risk assessment of the risks employees face, including the risk of work-related stress, in the same way an organisation would assess any other workplace hazard.

The case that put real weight behind this duty is Walker v Northumberland County Council [1995] IRLR 35. A social services manager suffered a nervous breakdown from an excessive caseload, returned to work on the understanding that support would follow, received none, and suffered a second breakdown that ended his career. The court held the council was not liable for the first breakdown, which was not reasonably foreseeable, but was liable for the second, because by then it had clear notice of his vulnerability and failed to act. The lesson for employers has held for three decades: a first sign of stress-related harm creates a duty to respond, and failing to do so exposes the organisation to negligence claims for whatever follows.

Where stress leads to a diagnosed mental health condition that is long-term, generally meaning 12 months or more, and has a substantial adverse effect on day-to-day activities, it can also meet the legal definition of disability under the Equality Act 2010. That triggers a separate duty to make reasonable adjustments, and treating a stress-related absence purely as a performance or attendance issue, without considering whether it meets that threshold, is a common and avoidable source of legal risk.

Management Standards: the six areas that drive stress

HSE’s Management Standards are not a campaign or a slogan. They treat stress like any other workplace risk: identify the hazard, assess who might be harmed, and put proportionate controls in place, across six areas of work design.

Standard	What it covers	A practical starting point
Demands	Workload, work patterns and the working environment	Review workloads regularly against realistic capacity and skill, not just headcount on paper
Control	How much say someone has over how they do their work	Build in genuine autonomy over pace, method or order of tasks wherever the role allows it
Support	Encouragement and resources available from managers and colleagues	Train managers to hold regular, supportive conversations, not just an annual review
Relationships	Positive working relationships, and addressing bullying or conflict	Resolve conflict early, through mediation, before it hardens into a grievance
Role	Whether people understand their responsibilities and avoid conflicting demands	Clarify role expectations explicitly, and revisit them whenever a team changes
Change	How organisational change is planned, communicated and managed	Involve people early, explain the reasoning, and set a realistic timeline

Recognising the signs early

Stress affects people differently, and there is no single reliable indicator. A change from someone’s normal pattern is usually more telling than any individual sign in isolation.

Withdrawal from colleagues, increased irritability, or a noticeable change in mood or energy.

A rise in short-notice absence, lateness, or unexplained gaps in an otherwise consistent attendance record.

A decline in the quality or pace of work from someone who has previously performed consistently well.

More frequent friction or conflict with colleagues, particularly from someone who does not usually raise issues.

Visible tiredness, difficulty concentrating, or comments about feeling overwhelmed, even made in passing.

Where stress and conflict meet

Of the six Management Standards, relationships is the one most HR teams underinvest in, largely because it is treated as a separate problem from stress rather than a leading cause of it. The connection is well evidenced. Acas research into workplace conflict found that 57% of people who experienced conflict at work went on to report stress, anxiety or depression as a result, making conflict one of the more direct and preventable drivers of the HSE figures above.

CMP’s own view, set out in more detail in our piece on focusing on the root causes of workplace mental health, is that psychological safety, the ability to speak up and raise a difficult issue before it festers, does more for genuine wellbeing than any wellness initiative layered on top of an unresolved culture. A stress policy that does not also give people a credible, accessible route to resolve conflict early, through a facilitated conversation or workplace mediation, is only addressing half the problem.

Common mistakes employers make

Treating stress as an individual resilience issue rather than a feature of how work, workload and relationships are actually structured.

Running a stress risk assessment once, as a compliance exercise, rather than making it a routine part of ongoing management practice.

Waiting for a formal grievance or a period of sickness absence before responding to signs that were visible much earlier.

Failing to act once a manager has clear notice of a problem, which is precisely the gap that created liability in Walker v Northumberland County Council.

Investing in wellbeing initiatives while leaving unresolved workplace conflict, one of the most direct drivers of stress, unaddressed.

Getting it right

Managing workplace stress well means treating it as a structural, ongoing risk rather than a series of individual cases to react to. CMP supports that with training that builds conversational and management skills, workplace mediation to resolve the relationship breakdowns that are often at the root of stress-related absence, and independent investigation where a complaint has already escalated and needs a fair, evidenced process.

You can read more about our approach and experience, or get in touch to talk through a current situation before it escalates further.