3CX integration

Overview

This guide shows how to connect 3CX - a popular software-based PBX - to Vobiz as a SIP trunk provider, enabling your 3CX phone system to make and receive calls through Vobiz numbers globally.

Prerequisites

Part 1: Vobiz setup

Create a SIP trunk

1. Log in to the Vobiz Console

2. In the left sidebar, navigate to SIP Trunk > Outbound Trunks > Trunks

3. Click + Create Trunk

4. Enter a Trunk Name (for example, "3CX Integration") and an optional Description

5. Under Authentication & Linking, select a Credential from the Credentials List - or click + Create New Credential if you don't have one yet

6. Click + Create Trunk to save

After creating the trunk, copy the following values from the Authentication & Linking section - you will paste these into 3CX in the next step:

✅ Success: You now have a Vobiz SIP trunk ready to accept registrations from 3CX.

Configure inbound routing (optional)

If you want 3CX to receive inbound calls on your Vobiz number, you need to point the trunk's inbound destination to your 3CX SIP URI.

1. In the Vobiz Console, go to your trunk and note the Inbound Destination field.
2. You will fill this in after completing the 3CX setup in Part 2.

Part 2: 3CX setup

Add Vobiz as a SIP trunk

1. Open the 3CX Management Console (typically at https://your-3cx-host:5001)

2. In the left sidebar, go to SIP Trunks

3. Click Add SIP Trunk

4. Under Country, select your country

5. Under Main Trunk No., enter your Vobiz phone number in E.164 format (for example, +918071387434)

6. Under Provider in your Country, choose Generic (scroll to the bottom of the list if it is not immediately visible)

7. Click OK to proceed to the trunk configuration form

Configure the trunk details

Fill in the following fields on the trunk configuration page:

⚠️ Warning: Do not include sip: or any URI scheme in the Registrar / Server field. Enter only the hostname (e.g., abc123.sip.vobiz.ai).

Configure outbound caller ID

Under the Outbound Parameters tab:

• Set Outbound Caller ID to your Vobiz phone number in E.164 format
• Leave Outbound Call Routing as the default unless you have a custom dial plan

Save and apply

Click OK to save the trunk. 3CX will attempt to register with the Vobiz SIP server. The trunk status should turn green (registered) within a few seconds.

✅ Success: A green trunk status confirms that 3CX has successfully registered with Vobiz.

Part 3: Configure inbound DID

To route inbound calls from your Vobiz number to a 3CX extension or ring group:

1. In the 3CX Management Console, go to DIDs

2. Click Add DID

3. Set DID number to your Vobiz phone number (E.164 format)

4. Set Destination to the extension, ring group, or IVR that should answer inbound calls

5. Select the Vobiz trunk from the Trunk dropdown

6. Click OK to save

Point Vobiz inbound to 3CX

Now go back to the Vobiz Console and update your trunk's inbound destination to your 3CX SIP URI:

1. In the Vobiz Console, open your trunk

2. Find the Inbound Destination field

3. Enter your 3CX SIP URI - this is the public IP or hostname of your 3CX server (for example, your-3cx.example.com or the IP address of the 3CX host)

4. Save the trunk

ℹ️ Note: For 3CX cloud-hosted installations, use the SIP domain shown in Settings > SIP within the 3CX console. For self-hosted, use the public IP or FQDN of your 3CX server.

Part 4: Test the integration

Test outbound calling

1. Pick up a 3CX extension (desk phone, softphone, or the 3CX mobile app)

2. Dial an external number in full E.164 format or using your standard dial plan

3. The call should route through Vobiz and connect

Test inbound calling

1. Call your Vobiz phone number from an external phone

2. The call should ring on the 3CX extension or ring group you configured in the DID settings

Troubleshooting

Trunk shows "Not Registered" or red status

Outbound calls fail or get "no route" error

• Verify the Outbound Caller ID matches your Vobiz phone number exactly (E.164)
• Check that the Outbound Call Routing rule includes a Vobiz trunk as the provider
• Confirm your Vobiz account has sufficient balance

Inbound calls do not reach 3CX

• Confirm the Vobiz trunk Inbound Destination points to the correct 3CX public IP or domain
• Make sure the DID in 3CX matches the incoming number format (E.164)
• Check that UDP port 5060 is open inbound on your 3CX server or firewall

SIP 401 Unauthorized

• Verify credentials in the Vobiz Console under SIP Trunk > Credentials
• Ensure the 3CX trunk Authentication ID matches the Vobiz credential Username exactly

Quick reference

Resources

Vobiz

• SIP Trunks
• Phone Numbers
• SIP Credentials
• Balance & Billing
• Console

3CX

• 3CX SIP Trunk Setup
• 3CX DID Configuration
• 3CX Network Configuration

Support

• Vobiz: support@vobiz.ai
• 3CX: 3cx.com/support

✅ Success: Integration complete!

Your 3CX phone system can now make and receive calls through Vobiz across 130+ countries.