Why this matters.
Workers who raise concerns about wrongdoing are protected by the Public Interest Disclosure Act 1998, which inserted Part IVA into the Employment Rights Act 1996. A worker who makes a protected disclosure cannot lawfully be subjected to detriment, and a dismissal because of whistleblowing is automatically unfair with no qualifying service period. Compensation for whistleblowing detriment and dismissal is uncapped, which makes it one of the costliest employment tribunal risks for a small business.
There is no legal requirement for most private employers to have a whistleblowing policy, but the tribunal will look closely at how you handled a concern, and regulated firms have additional duties under FCA and PRA rules. The Employment Rights Act 2025 also adds sexual harassment to the list of matters that can be a protected disclosure. A clear policy, a trusted reporting route and good records show you took a concern seriously and protect you if a claim is made.