Outbound Faxing Feedback

Hello All,

I just have a simple question and looking for some feedback. I have a customer On FreePBX Latest 5.x path, using SIP trunks for inbound/outbound. I have a test inbound DID for faxing that is working well.

They would like to move the last POTS line currently used for faxing to the SIP trunks and be done with the expense of POTS altogether. The relation of incoming to outgoing faxes is 90/10 respectively with very little outbound faxing, however they do use it from time to time.

The plan is to use a scanner to scan the pages for outbound and use the FreePBX Fax Pro module to send the faxes. SO now the question (finally), can anyone using the FaxPRO module and outbound faxing chime in and let me know what you are seeing with it, specifically:

  • What issues do you see?
  • Is it reliable?
  • Is it easy to use?

any and all feedback is MUCH appreciated!



Referring to SIP Trunks for Incoming/Outgoing calls, you then wrote:

Does this also mean that you tested FoIP (FAX over IP) on that dedicated DID over SIP Trunk?

If so and if it’s working flawlessly (no issue on incoming/outgoing FAXes with T.38 and with bandwidth/codecs) this is a great starting point. FoIP requires reliable and well configured SIP Trunks (with T.38 support) if compared to traditional FAXing through Analog (or Digital) Lines and FreePBX FAX Pro module has no part in granting that. FoIP is sensible - like (or more) VoIP over WAN - to Jitter, CoDecs transcoding (it prefers G.711 64kbps and dislikes compressing CoDecs used on VoIP calls) and available Bandwidth.

The only issue I see is the FoIP implementation itself (it should be planned/tested with you VoIP Service Provider).

See answer given above: if FoIP is OK (tested) then FreePBX FAX Pro should work flawlessly, if FoIP is not OK, then you can’t expect FreePBX FAX Pro to work as expected (it will send FAXes but your SIP Trunk will break them; it will wait to receive incoming FAXes if your SIP Trunk manages them correctly as usually happens with Analog/Digital Lines, if not it will be not able to receive any FAX or, at best, it will receive corrupt FAXes).

Quite easy from ARI Portal (the user portal) in FreePBX Distro 5.211.65. Not tested in FreePBX Distro 6.12.65 with the new UCP (new User Control Panel). FreePBX FAX Pro enhancements and new feature requests (see Issue portal and look for Tickets opened about FAX Pro) are evaluated.

If you plan to use FreePBX FAX Pro on FreePBX Distro 5.211.65 to send FAXes from ARI it will be quite simple (there are few things IMHO that should be adjusted - some features are absent, like having an hook to Asterisk phonebook, but, probably, those will be managed on FreePBX Distro 6.12.65); the workflow is quite simple: FAX enabled user logins to ARI, set a Cover Sheet (if custom, otherwise the user is able to use the general Cover Sheet of the company, if yet configured), upload PDF (or TIFF), write the recipient FAX number (remember: no hook to phonebook actually) and you’re OK.

Hey great info and thanks for the detailed reply…

Currently incoming faxing seems to be working 100% over the dedicated DID. My understanding though is outgoing seems to be the tricky part and can have issues.

I like what you are saying about the user side, seems easy enough and I am on the 5.211.65 track, -14 to be exact.

Is there an easy (or even a not so easy) way to test outbound without the FaxPRO module? I can certainly look it up, but thought I would ask, as Im typing anyway! :smile:

Again, thanks for the feedback, much appreciated!


I think there isn’t a “demo mode” to test FreePBX FAX Pro (Commercial) module before purchasing its license. At least as far as I know.

Basically FreePBX FAX Pro, once licensed and enabled, will provide a system wide FAX Configuration section on FreePBX GUI with these items (I’m not able to take a full screenshot of the long web page):

Fax Options

  • Fax Presentation Options

Default Fax header:
Default Local Station Identifier:
Outgoing Email address:

  • Fax Feature Code Options

Email address:

  • Fax Transport Options

Error Correction Mode
Maximum transfer rate
Minimum transfer rate

  • Fax Module Options

Always Allow Legacy Mode:

  • Fax Cover Page Options

Company Logo:
Company Name:
Company Address 1:
Company Address 2:
Company Address 3:
Company Phone:
Company Web Site:
Company Footer:
Preview Cover Page

  • User Control Panel Faxing Options

Global Prefix:

  • Failure Recovery Options


  • Failure Notification Options

Email Results:

  • Local Storage Options

Max Pages:
Excess Faxes

There is also a FAX section on each Extension.

The FAX section on ARI (user portal) should look like the screnshoot below (actually on FreePBX Distro 5.211.65 it is quite basic, as you can see):