Forward AT&T Voicemail to Google Voice

Let's say you have an iPhone, and you don't want to use Visual Voicemail, but prefer a different service. After much searching, and conflicting information, I found a procedure which appears to work.

First check your current Voicemail settings:

*#61# Call

Interrogate your forwarding settings.

Record the phone number where
Unanswered calls are forwarded.

Record the information that's presented, specifically the phone number your Voicemail current goes to. You should be able to reset everything later, but this is good confirmation that a reset gets you back to your original Voicemail settings.

Now configure it to forward your Voicemail to your Google Voice number. When Google Voice knows to record Voicemail when this happens. In the following sequence, be sure to replace the phone number with your own Google Voice number:

**61*+14085551234*11*30# Call

Forward your unanswered calls. Be sure to use
your own Google Voice number, not 408-555-1234.

Note the number 30 at the end; you can change this value to 5, 10, 15, 20, 25 or 30. That's how many seconds your phone will ring before it's forwarded to Voicemail.

Now you can retrieve your settings again and validate that it all worked:

*#61# Call

Update:
From Dacoach in the comments, here is the complete list:

• Immediate Call Forwarding: Dial *21* plus the 10-digit number to which your calls should be forwarded and #. Press Send.
• Busy Call Forwarding: Dial *67* plus the 10-digit number to which your calls should be forwarded and #. Press Send.
• Call Forwarding No Reply: Dial *61* plus the 10-digit number to which your calls should be forwarded and #. Press Send.
• Call Forwarding Not Reachable: Dial *62* plus the 10-digit number to which your calls should be forwarded and #. Press Send.