How can I forward Google Voice to my iPhone but still use the iPhone's visual voicemail?

Question

I have a Google voice number which forwards to my iPhone's number. I'm wondering if there's any way to make AT&T handle the voicemail rather than Google Voice. This way I will be able to use the Phone app to view voicemails rather than having to open a browser with Google Voice.

I understand that if I use it this way I won't get transcribed voicemail. That's fine, that's not the reason I'm using Google Voice.

Ideally I want Google Voice to handle voicemail when my phone is off or in airplane mode, and when my phone is on and I have a signal, I want it to use my phone's answering machine. This way I get notified of voicemail via WiFi when airplane mode is on, but when my cell signal is on, I get to use the nicer interface of the Phone app.

Answer 1

In order to do this, the iPhone's voice-mail system must pick up the call before the Google Voice voice-mail system does.

If you don't respond to a call within 25 seconds (by accepting, sending to voicemail, listening in on voicemail, or accepting and recording the call), Google Voice will send the caller to Google voicemail.

Source

You can set your iPhone to ring from 5-30 seconds (unless it has been changed since I've looked at this). The default is 20 seconds I think - have you previously lengthened it?

This page has instructions on how to change the length.