Session Initiation Protocol (SIP) is used in Voice over Internet Protocol (VoIP) communications. It usually allows users to make free voice and video calls over the Internet. A free SIP account is a great way to make free calls. You start by choosing a SIP provider who will assign you a free SIP account. Use it with softphone software, an app, or a VoIP-compatible phone.

OnSIP is a paid VoIP service offered by Junction Networks. However, the company also offers the OnSIP Free Plan for people who want to create a free SIP address. The OnSIP Free Plan offers a web-based voice, video, and messaging solution for teams. Features include:

The free OnSIP subscription replaces the company's GetOnSIP program.

SIP2SIP is a simple SIP service provided by AG Projects. It is a free SIP service based on a fair use policy. Registration and account management are easy. AG Projects provides this free SIP service as a way for users to test the features in its products. Using one of the compatible apps or clients, you can: