Set Up AT&T Phone To Use Google Voicemail
Google has it wrong. They tell you to use **004*googlevoicenumber# to turn voicemail on and ##004# to turn it off. Actually, that sets up forwarding of all calls to Google Voice. With this setup your phone will never ring and calls go directly to Google voicemail. Texts and data calls are forwarded as well, so you'll never see those either.
If you've already followed Google's instructions before reading this then it's too late, but if not, then first thing to do is to dial "*#61*11#" on your phone to get the phone number of the AT&T voicemail system that your phone is currently using. You'll need this number if you ever want to take your phone off Google voicemail and move it back to AT&T voicemail. In my case, that number is 18324219997. I don't know if yours will be the same. To test, just call that number from your phone. If you enter the voicemail system, then you're good.
These are the real call forwarding setup codes, thanks to Scott Cate.
The general input patterns are:
- Turn the service off: ##<code># or ##<code>*11# and press send
- Turn the service on: **<code>*<googlevoicenumber>*11# and press send
- Toggle service off/on: **<code>*11# and press send (It remembers the forwarding number you're using)
- Current status: *#<code>*11# and press send
The codes are:
- Forward all calls, all types (voice, data, fax. SMS, and four more) - 002 or 004 (Leave out the "*11" part of the code string with these two. Don't use these except to turn off all types of forwarding with one single input string.)
- Forward voice calls only - 21 (Calls are forwarded directly, your phone never rings)
- Forward after ring/no answer - 61 (Specify how long to ring before forwarding by adding "*NN" to the end of this code string just before the final "#", where NN is a number of seconds. 15 seconds is the out-of-the-box setting.)
- Forward when phone is unreachable - 62 (For when your phone is off / out of area)
So to get Google voicemail on your phone you really need to set the last two of those, 61 and 62. Unset 004 first if you followed Google's instructions before reading this.
Use your full eleven-digit phone number, 1 + area code + number, for <googlevoicenumber>. For some users this number may not be your actual Google Voice number. Check the "Activate Google voicemail on this phone link" on your Google Voice Settings -> Phones page to confirm the number. (That link doesn't actually do anything other than show you the codes to use to activate/deactivate Google voicemail so you can click away on it without concern.)
Other unknown codes:
- 31 = "Calling Line ID Restriction"