It's not illegal, but there are technical standards that make it impossible in most bathrooms. Sockets are allowed in British bathrooms provided they are 3 meters or more away from the water sources (taps in the sink or bath as well as showers). Shaver-supply units are the single exception to the standard.

It is not strictly "illegal" to have a plug socket in a UK bathroom, but it is heavily regulated under British Standard BS 7671 (The Wiring Regulations), specifically for safety in "special locations." In 2026, the law stipulates that a standard 13-amp socket-outlet is only permitted in a bathroom if it can be installed at least three metres (3m) away from the edge of the bath or shower (Zone 1/2 boundary). Because most UK bathrooms are too small to accommodate this distance, you rarely see standard sockets in them. However, shaving-supply units (which are current-limited and contain an isolating transformer) are legally allowed within Zone 2 (60cm from the water source). Any electrical work in a bathroom must be carried out by a Part P registered electrician to ensure it complies with building regulations and is properly RCD-protected. Failure to follow these rules can make it difficult to sell your home and, more importantly, poses a significant risk of electric shock in wet environments.