The protection of communication privacy covers not only the content of the conversation, but also other information related to the communication (metadata). The most prominent type of metadata in online communication is IP address, which defines the location of a computer or other connected device in the network. As a purely technical information, an IP address does not refer directly to any individual and is not in itself personal information. Yet, it can also be used to identify individuals online, track their location and online activity. An IP address is never strictly private, since any internet user’s IP address is visible to other participants in regular online interactions, which differentiates it from typical private information. The paper examines the conditions, developed in case law of the European Court of Human Rights and Court of Justice of the European Union as well as the Slovenian courts, under which an IP address can be considered personal data and when it is protected as a part of one’s communication privacy. The paper then focuses on the issue of whether an individual should be considered to have waived the privacy protection of their IP address if they have taken no measures to hide it. The relevance of the distinction between static and dynamic IP addresses from the perspective of privacy protection is also discussed.