Google has recently announced some upcoming changes to Google Voice. These will be going into effect on October 1st and perhaps more important -- is that they will be dealing with security. Specifically, with the security of your voicemail when you are calling in to access your account by phone.
Current Google Voice users will be greeted with a pop-up the next time they access their account online. The message is short, to the point and can be seen in the image below. Tapping the learn more option will take you over to the Google Voice support pages where you get a bit more detail in terms of what this means for the user.
Google has said that as of October 1st, if you need to access your account by phone you will need to call from one of your verified forwarding numbers. Of course, knowing that is likely not always possible -- there is also another option available. That other will give you access by entering a PIN code, which is getting improved a bit.
It was said that as of October 1st you will be able to extend your PIN from a maximum of four digits to ten digits. Simply put, once this change goes into effect you will be able to use a 10-digit PIN code as opposed to a 4-digit PIN code. While that may be slightly more difficult to remember, it should also make it a bit harder for others to guess.
That being said, those looking to change their PIN code once this new change goes into effect will be able to do so by navigating to their Google Voice account and heading to Settings -> Voicemail & Text -> Voicemail PIN. From here just enter the new PIN number two times and click the "save changes" button on the bottom of the page.
SOURCE: Google Voice