Your PIN gives you access to Google Voice settings and voicemail from multiple phones.
If you're using Google Voice with a Google number: your PIN allows you to access your voicemail by dialing your Google number from any phone, pressing * and entering your PIN. If you call your number from a phone from which you connect directly to voicemail, you may have to enter your PIN to access your messages, depending on the settings you've set up on the Phones tab of your Google Voice Settings.
If you're using Google Voice with a non-Google number: your PIN gives you access to Google Voice settings and voicemail from the phones you've registered in the Phones tab of your Google Voice Settings. If you call your Google voicemail access number from a registered number, you may have to enter your PIN to access your messages, depending on the settings you've set up on the Phones tab. You can access your Google voicemail from any phone by calling the mobile phone and going to voicemail. During the voicemail greeting, press * and enter your PIN.
To change your PIN, sign in to Google Voice and click the Settings link at the top-right of the page and select the Voicemail tab. In the Voicemail PIN section, enter your new PIN and re-enter the new PIN to confirm it. Then, click Save Changes.
