Explain use of existing phone number vs. Google Voice number

[zqz]

Brief background: Received Invite from Google and already have a spare Nexus 6P (unlocked, never used, new-in-the-box).

I read these support notes, https://support.google.com/fi/answer/6246240?hl=en&ref_topic=4596407

Based on those, my existing/current Google account which has a Google Voice number (and is used on a SG 4 Active AT&T device), would either become inactive or should be moved over to another Google account or a new Google Voice number should be requested - did I understand that correctly ?

Also, a friend locally got invice and simply moved over existing ATT number to Project FI with a new Nexus 6P but does not use Google Voice. What ? Is it not required ? When he travels to EU from US, he says he will continue to use his old #, now just moved over to another carrier pair but I understood that you must have a Google Voice number in addition to your existing carrier number ?

Thanks ahead for setting me straight.

 

[mogelijk]

Maybe the easiest way to understand this is to say that Project Fi replaces Google Voice when you activate the SIM. So, if you have Google Voice, the Voice account is converted into your Project Fi account and your old Voice number becomes your Fi number, unless you request to have a number transferred or a new number. If you transfer/request a new number, you lose your old Google Voice number. To save your old Google Voice number, but use a different number under Project Fi, you either need to create a new Google account to use with Project Fi, or transfer your Google Voice number to Google Voice under a different Google account.

Having Google Voice is not required, Google will merely create a new account under that Google ID, rather than convert the Google Voice account -- though the user will not be able to create a Google Voice account since he is a Fi user. Additionally, you cannot use a Fi account with a Google Voice account, the two will not work together (in the same way a Google Voice account doesn't work with another Google Voice number).

Typically, when you quit Fi, your Fi account reverts to Google Voice. I'm unclear what happens to those that didn't have a Google Voice account previously; though I suspect that their Fi account is converted over to a Voice account -- the exception would be if they port their Fi number to another carrier.

 

[zqz]

So what happens if I take BOTH my existing AT&T number AND my Google Voice(GV) number over to Project FI ?

You did say that existing GV becomes the number to use, OK - then how and what happens to my existing carrier number(ECN) which today is billed by AT&T but in effect all calls goto GV ? Does that ECN number simply disappear and it serves no purpose ?

If I then decide to leave Project FI, yes, I did read steps on porting it back but did I just manage to "lose" my old AT&T cell number when I moved over to Project FI ? (Have not done this yet, thus the queries). Am also not quite clear how my traveling friend is NOT using GV but simply moved his AT&T number over to P_FI and Nexus 6P as based on everything he should now have a new GV number, never before having used GV.

 

[mogelijk]

If you have your AT&T number transferred to Fi, it will take the place of your Google Voice number, you will lose that number permanently unless you use a different Google account for Fi than your Google Voice number is on.

As for your friend, you can't have both a Project Fi number and a Google Voice number on the same account. Since he is on Fi, he cannot get a Google Voice number on that account.

As I understand it, you can almost think of Project Fi accounts as a "premium" Google Voice account. Google Voice is a virtual phone number -- one not tied to any physical device -- that Google sets up, allowing you to use that number as a forwarding service for the other phones you own. Fi takes the Google Voice account but makes the phone number "real", tied to your Fi SIM. Basically, Google is using the code they created to set up the Google Voice accounts to set up Project Fi accounts; just they manage the accounts separately. Because of this, you can't have Google Voice and Project Fi both on the same account.