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This guide walks you through connecting your Telnyx phone numbers using SIP trunking. You’ll create an FQDN connection in Telnyx, configure outbound authentication, assign your numbers, and import them into the platform.
One-time setup: You only need to create the SIP connection once (Steps 1–5). For each additional phone number after that, you simply assign it to your existing connection (Step 5) and import it (Step 7).
Why FQDN? The connection type must be FQDN — not Credentials or IP Address. Credential connections require SIP REGISTER for inbound calls, which our platform doesn’t send. FQDN connections route inbound calls directly to our SIP server and authenticate outbound calls via credentials.

Step 1: Create SIP Connection

  1. Log in to the Telnyx Mission Control Portal
  2. Navigate to Real-Time CommunicationsVoiceSIP Trunking
  3. Click Create SIP Connection
  4. Name: Choose a name (e.g., my-company SIP trunk)
  5. Type: Select FQDN
  6. Click Create — this opens the setup wizard
    Create SIP Connection in Telnyx

Step 2: Authentication and Routing

The wizard takes you to the Authentication and routing step. Here you’ll add the FQDN for inbound call routing and set up outbound credentials.

Add FQDN

  1. Click ”+ Add FQDN” and enter:
    • DNS Record Type: A
    • FQDN: 5wed79aeavr.sip.livekit.cloud
    • Port: 5060
  2. Click Save
    Add FQDN to Telnyx connection

Inbound Calls Routing

Scroll down to the Inbound calls routing section on the same page:
  1. SIP subdomain: Enter a name (e.g., yourcompany) — this creates yourcompany.sip.telnyx.com
  2. Receive SIP Subdomain calls: Set to From Anyone
  3. Primary FQDN: Select 5wed79aeavr.sip.livekit.cloud from the dropdown
    Configure inbound calls routing

Outbound Authentication

Scroll down further to the Outbound calls authentication section:
  1. Method: Select Credentials
  2. Set a username and password — save these, you’ll need them when importing the number into the platform
    Set outbound credentials
Click Next at the bottom of the page.

Step 3: Configuration

The wizard shows the Configuration page with connection details, webhooks, and advanced settings. You don’t need to change anything here — just verify that the Type shows FQDN Connection and click Next.
Configuration page

Step 4: Inbound and Outbound

The wizard will go through the Inbound and Outbound steps. Since you already configured these in Step 2, verify the settings are correct and click Next on each. On the Outbound page, make sure:
  1. Outbound voice profile: Select your profile (or “Default”)
  2. Localization country: Select your country
  3. Channel limit: Set to 10 or higher
    Configure outbound settings
If you don’t have an Outbound Voice Profile, go to VoiceSettingsOutbound Voice ProfilesCreate Profile. Make sure to enable the countries you want to call under Allowed Destinations.

Step 5: Assign Numbers

The last step of the wizard is the Numbers page:
  1. Click Assign numbers
  2. Select the phone number(s) you want to use

Step 6: Enable Geographic Permissions

  1. Go to VoiceSettingsOutbound Voice Profiles
  2. Click on edit
    Enable geographic permissions
  3. Click on your profile → Allowed Destinations
  4. Enable the countries/regions you need to call
    Enable geographic permissions
If you skip this step, outbound calls will fail with a 403 error: “Dialed number is not included in whitelisted countries.”

Step 7: Import Number to the Platform

  1. Go directly to the Phone Numbers page in your dashboard: https://app.autocalls.ai/phone-numbers If it takes you to the login page, log in first — it will automatically redirect you to the Phone Numbers page.
  2. Click “Integrate SIP trunk” (top-right corner of the page)
    Import number via SIP trunk
  3. Fill in your phone number and SIP credentials:
    Phone number: Your Telnyx number (e.g., +1 555 0123)
    Username: The outbound username from Step 2
    Password: The outbound password from Step 2
    
  4. Enter the outbound settings:
    SIP address: sip.telnyx.com
    Outbound format: International (with + in front)
    
    Configure outbound settings in Autocalls
SIP address must be sip.telnyx.com — do NOT use your SIP subdomain (e.g., yourcompany.sip.telnyx.com). The subdomain is only for inbound routing on the Telnyx side. Using it as the outbound SIP address will result in 404 Not Found errors.
  1. Select Authorization type: IP Address and add the Telnyx IP addresses for your region:
    • US: 192.76.120.10
    • Europe: 185.246.41.140 and 185.246.41.141
    • Australia: 103.115.244.145 and 103.115.244.146
    Configure inbound IP addresses
You can add all IP addresses regardless of region — only the relevant ones will be used.
  1. Select the country where your SIP trunk is located.
    SIP Country selection

Step 8: Verify Setup

To test your Telnyx number, you need to assign it to AI assistants. Inbound and outbound require separate assistants:

Test Inbound

  1. Go to AI Assistants → create a new assistant (or use an existing one)
  2. Set the assistant type to Receive phone calls
  3. Assign your Telnyx phone number to the assistant
  4. Call your Telnyx number from any phone — the AI assistant should answer

Test Outbound

  1. Create a second assistant with type Make phone calls
  2. Assign the same Telnyx phone number to this assistant
  3. Click Speak to assistantPhone call — the platform will call your personal phone using the Telnyx number
A single assistant cannot handle both directions. You need one Receive phone calls assistant and one Make phone calls assistant, both with the same phone number assigned.

Security Requirements

Your SIP credentials need to be secure:
  • Username: Your provider-supplied username
  • Password must have:
    • 12 or more characters
    • Numbers
    • Upper and lowercase letters
    • Special characters recommended

Common Issues

Go to VoiceSettingsOutbound Voice Profiles → your profile → Allowed Destinations and enable the destination country you’re trying to call.
  • Make sure the connection type is FQDN (not Credentials or IP Address)
  • Verify the FQDN is set to 5wed79aeavr.sip.livekit.cloud on port 5060
  • Check that the phone number is assigned to the FQDN connection (not another connection)
  • Verify the SIP address is sip.telnyx.com (not your SIP subdomain)
  • Check that credentials match between Telnyx and the platform
  • Make sure an Outbound Voice Profile is attached to the connection
  • Verify the Localization country is set correctly
Credential connections require SIP REGISTER for inbound calls. Our platform uses direct SIP routing (no registration), so FQDN connection type is required. FQDN still supports credential-based authentication for outbound calls.

Need help setting up? Our support team specializes in helping customers integrate their phone systems. We’ll guide you through the entire process, ensuring a smooth setup with your specific phone system configuration.