call waiting is a voice-telephony supplementary service that alerts a subscriber already on a call that a second inbound call is attempting to connect, allowing the user to end the original call, place it on hold, or switch between the two calls (and, depending on the service, divert or reject the new call). It is a descriptive telecommunications term rather than one typically defined in statute or case law; it is usually set out in network operators’ contract terms, product descriptions and technical standards, and referenced in regulatory frameworks overseen by Ofcom (UK) and ComReg (Ireland).
In practice, call waiting features in consumer and business telecoms contracts and service level agreements, policies on activation/deactivation, and billing. Key legal points include: availability and compatibility (for fixed-line and mobile; handset/network limitations), default settings and user control, any charges, and how the feature interacts with voicemail, call diversion and call barring. Across England & Wales, Scotland, Northern Ireland and Ireland, usage and meaning are broadly consistent, subject to operator-specific terms and applicable Ofcom/ComReg requirements on transparency, quality of service and complaints handling.