Telnyx SIP integration

Go to Voice / Outbound Voice Profiles
Create a new profile
Name it appropriately
Configure desired destinations
Leave default configuration settings
Assign your SIP trunk
Complete setup Alternatively, go to your SIP trunk / Outbound tab and select your newly created outbound voice profile.

3

Configure outbound settings

Choose the country you’ll be making most calls to We recommend creating a separate SIP Trunk for each country you aim to be making most calls to.

4

Add your Telnyx SIP credentials to Vapi

Use the Vapi API to create a SIP trunk credential:

Use IP addresses in gateways. FQDNs like sip.telnyx.com return a 400 Bad Request.

$ curl -X POST https://api.vapi.ai/credential \
>   -H "Content-Type: application/json" \
>   -H "Authorization: Bearer YOUR_VAPI_PRIVATE_KEY" \
>   -d '{
>     "provider": "byo-sip-trunk",
>     "name": "Telnyx Trunk",
>     "gateways": [
>       {
>         "ip": "192.76.120.10",
>         "inboundEnabled": true
>       },
>       {
>         "ip": "64.16.250.10",
>         "inboundEnabled": true
>       }
>     ],
>     "outboundAuthenticationPlan": {
>       "authUsername": "YOUR_SIP_USERNAME",
>       "authPassword": "YOUR_SIP_PASSWORD",
>       "sipRegisterPlan": {
>         "realm": "sip.telnyx.com"
>       }
>     }
>   }'

Replace YOUR_VAPI_PRIVATE_KEY, YOUR_SIP_USERNAME, and YOUR_SIP_PASSWORD with your actual credentials. Replace the gateway IPs with the Telnyx gateway IPs assigned to your trunk. Set inboundEnabled to false if you only need outbound calls. If successful, the response will include an id for the created credential, which you’ll use in the next step.

5

Add your phone number to Vapi

Associate your phone number with the SIP trunk in Vapi:

$ curl -X POST https://api.vapi.ai/phone-number \
>   -H "Content-Type: application/json" \
>   -H "Authorization: Bearer YOUR_VAPI_PRIVATE_KEY" \
>   -d '{
>     "provider": "byo-phone-number",
>     "name": "Telnyx SIP Number",
>     "number": "YOUR_PHONE_NUMBER",
>     "numberE164CheckEnabled": false,
>     "credentialId": "YOUR_CREDENTIAL_ID"
>   }'

Replace YOUR_VAPI_PRIVATE_KEY, YOUR_PHONE_NUMBER, and YOUR_CREDENTIAL_ID with your actual details.

6

Assign your voice assistant to handle calls

In your Vapi dashboard, go to the Build section and select Phone Numbers
Click on your Telnyx Number
In the Inbound Settings section, assign your voice assistant to handle incoming calls
In the Outbound Form section, assign your voice assistant to handle outgoing calls

7

Make outbound calls

To initiate outbound calls through your Telnyx SIP trunk:

$ curl --location 'https://api.vapi.ai/call/phone' \
>   --header 'Authorization: Bearer YOUR_VAPI_PRIVATE_KEY' \
>   --header 'Content-Type: application/json' \
>   --data '{
>     "assistantId": "YOUR_ASSISTANT_ID",
>     "customer": {
>       "number": "CUSTOMER_PHONE_NUMBER",
>       "numberE164CheckEnabled": false
>     },
>     "phoneNumberId": "YOUR_PHONE_ID"
>   }'

Replace all placeholder values with your actual information.

$	curl -X POST https://api.vapi.ai/credential \
>	-H "Content-Type: application/json" \
>	-H "Authorization: Bearer YOUR_VAPI_PRIVATE_KEY" \
>	-d '{
>	"provider": "byo-sip-trunk",
>	"name": "Telnyx Trunk",
>	"gateways": [
>	{
>	"ip": "192.76.120.10",
>	"inboundEnabled": true
>	},
>	{
>	"ip": "64.16.250.10",
>	"inboundEnabled": true
>	}
>	],
>	"outboundAuthenticationPlan": {
>	"authUsername": "YOUR_SIP_USERNAME",
>	"authPassword": "YOUR_SIP_PASSWORD",
>	"sipRegisterPlan": {
>	"realm": "sip.telnyx.com"
>	}
>	}
>	}'

$	curl -X POST https://api.vapi.ai/phone-number \
>	-H "Content-Type: application/json" \
>	-H "Authorization: Bearer YOUR_VAPI_PRIVATE_KEY" \
>	-d '{
>	"provider": "byo-phone-number",
>	"name": "Telnyx SIP Number",
>	"number": "YOUR_PHONE_NUMBER",
>	"numberE164CheckEnabled": false,
>	"credentialId": "YOUR_CREDENTIAL_ID"
>	}'

$	curl --location 'https://api.vapi.ai/call/phone' \
>	--header 'Authorization: Bearer YOUR_VAPI_PRIVATE_KEY' \
>	--header 'Content-Type: application/json' \
>	--data '{
>	"assistantId": "YOUR_ASSISTANT_ID",
>	"customer": {
>	"number": "CUSTOMER_PHONE_NUMBER",
>	"numberE164CheckEnabled": false
>	},
>	"phoneNumberId": "YOUR_PHONE_ID"
>	}'