It allows users to make mostly free voice and video calls online.

Having a freeSIPaccount is a great way to make free calls.

You begin by choosing an SIP provider to assign you an SIP accountat no charge.

Person using voice call headset

Using a voice call headset via VOIP/SIP.Alistair Berg / Getty Images

Use it withsoftphonesoftware, an app, or a VoIP-compatible phone.

SIP2SIP

Free and easy to use.

Consumer-facing usage doesn’t seem to be the developer’s priority.

SIP 2 SIP website

Separate apps for video and audio.

SIP2SIP is a straightforward SIP service offered by AG Projects.

It is a free SIP service based on a fair-use policy.

Antisip website

Registration and account management are easy.

Using any of the compatible apps or clients you might:

AntiSIP

Pure SIP-to-SIP provider.

The Antisip service offers a set of SIP-based services.

onsip website

Among them is a free SIP account that provides VoIP-to-VoIP services.

Links to YouTube tutorials are available on the website for users who are new to the SIP experience.

OnSIP Free Plan

Plan includes 100 users with unlimited extensions; great for teams.

Slack and Zendesk integrations.

system suite can be a bit difficult to navigate.

Still some documentation updating after the GetOnSIP migration to the OnSIP Free Plan.

OnSIP is a paid VoIP service offered by Junction Networks.

The OnSIP Free Plan provides a web-based voice, video, and messaging solution for teams.

The features include:

The OnSIP Free Plan replaces the company’s GetOnSIP program.