Hi all – I’m working on integrating VAPI with a 3CX system for a client (estate agent) and could use some help. The aim is to connect a VAPI voice agent to a 3CX SIP extension, not the main inbound phone number. This is important because we don’t want to disrupt the client’s regular business phone service while we test and deploy. We also can’t move or repoint the main number, so we need to make this work through an internal extension. We’ve created a SIP extension on 3CX and entered the credentials into VAPI, but it’s not connecting successfully. In testing, either the call never reaches 3CX or it gets rejected. We’ve verified that the SIP credentials work in other softphone tools, so we know the account itself is functional. Has anyone here successfully connected VAPI to a 3CX extension? I’d really appreciate any tips—particularly around: Correct setup of SIP credentials in VAPI Any 3CX settings that might block or interfere with the connection Best way to test the integration without touching the main phone number Thanks in advance for any help or pointers—really hoping someone here has made this work before.

@Gavin I've tried doing this myself a while back, and reached a conclusion the way 3CX works isn't compatible here. The primary reason is that 3CX views the world one way, while VAPI (and other platforms) views it another. I managed to connected 3CX to VAPI via our Cloudonix platform, with some annoying caveats. Here is a link to document describing that integration path: https://developers.staging.cloudonix.com/Documentation/telephonyProducts/Vendor/3CX

Really appreciate your reply and shared link, thank you. My client claims to have the 'top package' for 3cx so i guess i need to find out if they can utilise custom call scripts.

exactly !

So there is no direct integration between Vapi and 3cx withouth a third party bridge?

Not as far as I managed to test and validate - 3CX is very much a "walled garden" platform, sorry to say. If you are not "partnered" with them, then integration with them can be a nightmare.

Just giving you my 2 cents.. I was successful in registering 3CX with VAPI. If you do manage to route calls to VAPI via 3CX, please let me know. https://cdn.discordapp.com/attachments/1373969078431256577/1413117113832312942/image.png?ex=68bac35e&is=68b971de&hm=1d2f0ad3f89eb6383555c3e775097481fd6c82413088ac9f2802aa364faabfd0&