How to Handle a Bullying or Harassment Complaint at Work
Take every bullying or harassment complaint seriously, acknowledge it promptly, decide whether it can be resolved informally, protect the complainant from further harm, investigate fairly, and tell both sides the outcome. Employers can be liable for harassment, including by third parties from October 2026, unless they took all reasonable steps to prevent it.
This post is for small business owners and managers who have received a complaint and want to handle it properly.
Bullying and harassment: what is the difference?
Harassment has a legal definition under the Equality Act 2010. It is unwanted conduct related to a protected characteristic, such as sex, race, disability or age, that violates someone's dignity or creates an intimidating, hostile, degrading, humiliating or offensive environment for them. Sexual harassment is a separate form, covering unwanted conduct of a sexual nature.
Bullying has no single legal definition, but it generally means offensive, intimidating or abusive behaviour that undermines or humiliates someone. It may not relate to a protected characteristic, but it can still lead to a grievance, a health and safety issue, a breach of the duty of trust and confidence and a constructive dismissal claim.
Whatever the label, the employer's response should be the same: take it seriously.
What the law expects of employers
Employers can be held responsible for harassment by their employees, whether or not they knew about it, unless they took all reasonable steps to prevent it. Employers also have a duty to take reasonable steps to prevent sexual harassment, and that duty has been in force since October 2024.
From October 2026, the Employment Rights Act 2025 also makes employers liable again for harassment of their staff by third parties, such as customers, clients and suppliers, unless they took all reasonable steps. These provisions are due to come into force in October 2026.
Since April 2026, a disclosure about sexual harassment can also qualify as a protected disclosure for whistleblowing purposes, which gives the person added protection against dismissal and detriment.
What to do when you receive a complaint
Acknowledge it promptly. Confirm receipt in writing, explain what happens next and who will deal with it.
Listen. Meet the person, let them describe what happened and, importantly, ask what outcome they want. Take notes.
Decide informal or formal. Some matters can be resolved by a conversation, mediation or an agreed change in behaviour. Serious allegations, or people who do not want an informal route, should go through the formal process. Do not push someone into an informal resolution.
Consider interim measures. If the person is at risk of further harm, you may need to separate people, change reporting lines or working arrangements. Be careful not to disadvantage the complainant. Moving them without agreement can look like punishment. Suspension of the person accused should be used only if necessary.
Investigate. Appoint someone impartial, which for a small business may mean an independent investigator. Speak to the complainant, the person accused and relevant witnesses, and collect documents.
Reach a decision. Consider the evidence on the balance of probabilities, and write down the findings and reasons.
Take action. If the complaint is upheld, this may include disciplinary action, training, changes to working arrangements or an apology. If it is not upheld, explain why.
Communicate the outcome to both parties, appropriately, and offer an appeal.
Follow up. Check in with the complainant after a few weeks to see how they are, and make sure nobody has been victimised.
Protect against victimisation
Treating someone badly because they complained is separately unlawful. The same applies to witnesses. Remind everyone involved, in writing, that retaliation will be taken seriously, and watch for subtle forms such as exclusion or changes in shifts.
Third-party harassment
If your staff deal with customers, clients, patients or contractors, you need to think about harassment from them as well. Practical steps include:
A clear policy that staff can report it
Making it easy and safe to report
Acting when it happens, for example by speaking to the customer, restricting contact or refusing service
Training managers to take it seriously
Preventing complaints
The best protection is prevention. That means a clear anti-harassment and bullying policy, regular training for managers and staff, a culture where people can raise concerns, and a risk assessment of where harassment is most likely. The duty is to take all reasonable steps, so write down what you do.
Time limits
For events on or after 1 October 2026, most tribunal claims, including harassment claims, have a six-month time limit. Where there is a series of incidents, the limit generally runs from the last one. A complaint you consider closed may therefore resurface months later.