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No. Google Voice does not support faxing: it has no T.30 or T.38 fax support, so transmissions fail or never start. A Voice number is virtual and carried over VoIP, and fax tones do not survive that trip. The workaround is to port the number to a fax-capable service, or keep Voice for calls and send faxes separately.
Fax was designed for continuous analog audio. Google Voice carries your call as compressed voice packets over the internet, and fax tones do not survive the compression and jitter. Google Voice also does not implement T.38, the protocol that makes fax-over-internet reliable, so there is no fallback: the handshake between the two fax machines never completes, and the transmission dies.
The same is true in both directions. You cannot reliably send a fax from a Google Voice number, and you cannot reliably receive one on it. This is not a setting you can flip: it is a missing capability in the service itself.
Yes, and this is the cleanest fix if the number itself matters to you. Google Voice lets you release a number for porting, after which you can move it to another provider. Once the number lives with a fax-capable provider, that provider's equipment answers incoming fax calls, and you can send from the number through their service.
A few practical notes: porting takes days, not minutes, and your Voice service on that number ends when the port completes. Do the porting on a quiet week, and keep a second way to reach you in the meantime. Also confirm the receiving provider actually supports fax before you start: many VoIP providers carry voice fine and fax badly.
| Option | What changes | Best when |
|---|---|---|
| Keep Voice, send faxes separately | Nothing: Voice stays for calls and texts | You fax rarely and like your Voice setup |
| Port the number to a fax provider | The number becomes a real fax number | The number is printed on your letterhead |
| Get a separate virtual fax number | You run two numbers side by side | You want fax without disturbing Voice |
| Fax from Gmail instead | Email-to-fax through a fax provider | You live in your inbox anyway |
If you just need to send the occasional fax, you do not need to move any numbers at all. LetterAgent's fax service sends outbound faxes to US and Canadian numbers without any hardware: you describe the fax to your AI assistant, approve the exact quoted total, and pay once through Stripe. Fax is in testing, and there is no inbound service, so it covers the sending side only.
| Step | What to do | Watch out for |
|---|---|---|
| 1. Release the number in Google Voice | In Voice settings, choose the option to port or release the number | There may be a small fee to release it; the Voice service on that number ends |
| 2. Pick the receiving provider | Choose a fax-capable provider and start a port-in request | Confirm they support fax, not just voice, before you begin |
| 3. Submit the port request | Give the provider your Voice account details and authorize the transfer | Details must match exactly or the port gets rejected |
| 4. Wait and test | Porting usually takes a few days | Send a test fax both ways before announcing the number |
During the move, keep a second way to reach you: calls to the number can behave oddly mid-port. And once the number lands, test it from a different fax source before telling clients it is live. A number that receives voice calls fine can still fail on fax if the provider's fax support is an afterthought.
Ready to fax it? Fax with LetterAgent: describe it to your AI assistant, approve the exact quoted price, and it is sent.
LetterAgent is a working name. Prices include print, postage, and our service fee. US prices in USD, Canadian prices in CAD (Canadian prices exclude applicable sales tax, added at checkout). Currently in private testing.
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