How to Forward Your Mobile Phone's Voicemail to Google Voice with a Full Google Voice Account (and Still Use Your Mobile Phone with Your Google Number)

Google recently announced the option to use Google Voice with your existing number.  By selecting this option when you sign up for Google Voice, Google Voice effectively becomes an enhanced voicemail service with capabilities like SMS alerting, archiving, and transcripts, but you lose out on many other great features like ringing multiple phones or ListenIn.  Given this, I'm not sure why anyone would want to sign up for this limited service.

Instead, you can sign up for a full Google Voice account and get Google Voice voicemail for your existing number--plus preserve the option to use all of Google Voice's other features with a new number if you like.  With this option, whether someone calls your mobile phone number or your Google number, Google Voice will handle your voicemail.

Here's how to setup your mobile phone to use Google Voice's voicemail with a full Google Voice account:

1. Sign up for a Google Voice account.  Note that you'll need an invite to join, currently
2. Select the option to create an account with a Google Number rather than a non-Google number
3. Add your mobile phone to your Google Voice account
4. Go to Settings in Google Voice and click on the "Activate Google voicemail on this phone" link
5. Follow Google Voice's popup instructions to forward your phone's voicemail to Google Voice
   
6. Go back to Settings in Google Voice and click the "Edit" link on the settings for your mobile phone
7. Click "Show advanced settings"
8. Under the "Forwarding Options" section, set "Go straight to voicemail."  This will ensure that Google Voice won't try to ring your other phones once your mobile phone has forwarded to voicemail

That's it!  Now, when someone calls your mobile phone number and you don't answer, it will go to Google Voice's voicemail--just like with Google's Google Voice With Your Own Number service.  But, you still have the option to switch to your Google number in the future and take advantage of all of Google Voice's other features.  So, for example, if someone calls your Google number, it will also ring your mobile phone.