[technofiend]

For some unfathomable reason Google no longer allows Google Voice clients to forward their calls to Project Fi numbers. So my new layer of abstraction is a $3/mo Call Centric number routed to a $12 SIP deskset.

Call Centric lets you whitelist so step one is to upload your contacts to them and then drop any calls not in your list. Goodbye telemarketers. Second step is to leave the phone unplugged altogether unless you need to use it since anyone you know has your mobile number anyway. :-)

If you really need it, you can add the Call Centric number to your cellphone via a SIP client but in my experience that's a bit of a battery sucker and call quality can be poor with noticeable voice delay.

[tylerl]

"No longer..."?

No, it never was possible. The two systems use the same underlying infrastructure but for different purposes, which leads to a frustrating interplay of technical constraints and security/privacy controls.

[technofiend]

I distinctly remember being able to do it at one time. Then a friend complained he could never reach me and I discovered my cell number was dropped from forwarding and couldn't be added back. I may have managed to sneak it in by porting in a forwarded number.