Make unlimited SIP calls to Google Voice number [Tutorial]

UPDATE (15th March 2011): After a brief outage the Google Voice SIP URI is working again

For an otherwise great great service, the lack of interoperability with SIP service mars the attractiveness of Google Voice. Up until recently, Google offered the ability to forward the Google Voice number to a Gizmo account, providing some way to extend the reach of GV. However, Google announced the termination of Gizmo5 service starting April 3, 2011. For many of us, using Gizmo5 to use Google Voice services on ATA or other soft phones, this is a huge blow. We recently reviewed Talkatone that lets you use Google Voice over 3G or WiFi without using local plan minutes. In this tutorial, we provide you another way to make calls to any Google Voice number using a SIP account for FREE. This tutorial is based on findings by Todd Vierling and is intended to be a step by step guide to call Google Voice numbers using SIP.

As you would expect, you need a SIP account and a SIP client (ATA or a SIP softphone) to make SIP calls. So, let’s get started…

Step 1: Create a FREE SIP account at Sip2Sip.info

Although any SIP account should work, I used Sip2Sip for this tutorial. If you don’t already have one, create a FREE account at Sip2Sip. For a free service, Sip2Sip is extremely capable service from AG Projects. (more on that in a separate post).

Step 2: Configure your SIP client

Now you need to configure your SIP account with a SIP client (ATA or SIP soft phone, e.g., x-lite). Please note that your SIP client should be able to dial SIP URIs. You can even use a mobile VoIP (mVoIP) client such as Media5-fone iPhone SIP client.  For the purpose of this tutorial, I am using Blink.

Blink is a very powerful SIP client and is well integrated with Sip2SIp, making it an ideal choice for this tutorial. You can download Blink here (both PC and Mac versions are available). Just enter your Sip2Sip account details and you are ready to make SIP calls, no need to enter any other SIP configurations.

To make SIP calls to Google Voice, just dial +1XXXYYYZZZZ@sip.voice.google.com, where XXXYYYZZZZ is the Google Voice number that you need to dial. Just dial the SIP URI and you will be connected with the Google Voice number that you dialed. The screenshots below will help:

Like everyone else, I am hoping that Google will provide SIP connectivity directly inside Google Voice so that we do not have to use such tricks. Till that happens, I am sure you will enjoy this trick to make free SIP calls to Google Voice without using local plan minutes.

Related posts:

1. How-to Enable SIP Support with Google Voice [Tutorial]
2. Make Google Voice calls without using local cell phone minutes using YateClient [Video Tutorial]
3. Talkatone: Save your local plan minutes, use Google Voice over 3G or WiFi [Video Tutorial]
4. WiMobile – Make unlimited free international calls to India, Italy, USA, China, and UK [Free Calls]
5. Use Whistle Phone on any SIP device – Make free VoIP calls to USA [Tutorial]