Dynamic SIP Trunking API

SIP Trunking is the product that connects your PBX, SBC, or SIP platform to Exotel PSTN.
Dynamic SIP Trunking is the REST API used to create and manage those trunks.

Use these APIs to make outbound calls (SIP → PSTN), receive inbound calls (PSTN → SIP), and integrate with Exotel Flows / StreamKit Voice AI.

Samples: Postman · GitHub

Base URL and authentication

All APIs use HTTP Basic Auth. Prefix every path with /v2/accounts/{account_sid}.

Region	Base URL
India (Mumbai)	`https://api.in.exotel.com`
Singapore	`https://api.exotel.com`

Header	Value
`Authorization`	Basic (`api_key`:`api_token`)
`Content-Type`	`application/json`

Rate limit: 200 requests/minute.

export EXOTEL_API_KEY="your_api_key"
export EXOTEL_API_TOKEN="your_api_token"
export EXOTEL_ACCOUNT_SID="your_account_sid"
export EXOTEL_SUBDOMAIN="api.in.exotel.com"   # or api.exotel.com

Response envelope

Successful calls return this shape (field names exact):

{
  "request_id": "10a67da360d446378d5c2b66407b7f18",
  "method": "POST",
  "http_code": 200,
  "response": {
    "code": 200,
    "error_data": null,
    "status": "success",
    "data": { }
  }
}

List endpoints wrap items in response[] and may include metadata (page_size, first_page_uri, prev_page_uri, next_page_uri).

Workflow

Create trunk → Map phone-numbers → whitelisted-ips and/or credentials → destination-uris

Direction	Requires
Outbound	Trunk + mapped DID + ACL and/or digest credentials
Inbound	`destination-uris` + Connect applet `sip:<trunk_sid>`

Number mode: pstn (default) · flow (Voice AI / StreamKit). See Call directions.

Endpoint index

Paths below are relative to /v2/accounts/{account_sid}.

Setup

Method	Path	Purpose
`POST`	`/trunks`	Create trunk
`POST`	`/trunks/{trunk_sid}/phone-numbers`	Map DID
`POST`	`/trunks/{trunk_sid}/whitelisted-ips`	Add ACL
`POST`	`/trunks/{trunk_sid}/credentials`	Create digest credentials
`POST`	`/trunks/{trunk_sid}/destination-uris`	Map inbound URI

Manage & view

Method	Path	Purpose
`GET`	`/trunks`	List trunks
`PUT`	`/trunks/{trunk_sid}`	Update trunk
`DELETE`	`/trunks?trunk_sid=`	Delete trunk
`GET`	`/trunks/{trunk_sid}/phone-numbers`	List mapped numbers
`PUT`	`/trunks/{trunk_sid}/phone-numbers/{id}`	Update `mode`
`DELETE`	`/trunks/{trunk_sid}/phone-numbers?id=`	Unmap number
`GET`	`/trunk-maps?exophone=`	Lookup DID → trunk
`GET`	`/trunks/{trunk_sid}/whitelisted-ips`	List ACLs
`PUT`	`/trunks/{trunk_sid}/whitelisted-ips/{id}`	Update ACL
`DELETE`	`/trunks/{trunk_sid}/whitelisted-ips?id=`	Delete ACL
`GET`	`/trunks/{trunk_sid}/destination-uris`	List URIs
`PUT`	`/trunks/{trunk_sid}/destination-uris/{id}`	Update priority/weight
`DELETE`	`/trunks/{trunk_sid}/destination-uris?id=`	Delete URI
`GET`	`/trunks/{trunk_sid}/credentials`	List credentials
`PUT`	`/trunks/{trunk_sid}/credentials/{id}`	Update credential
`DELETE`	`/trunks/{trunk_sid}/credentials?id=`	Delete credential
`GET`	`/trunks/{trunk_sid}/settings`	List settings
`POST`	`/trunks/{trunk_sid}/settings`	Set caller ID alias
`DELETE`	`/trunks/{trunk_sid}/settings?name=`	Delete setting

Setup APIs

Create trunk

POST/v2/accounts/{account_sid}/trunks

Request parameters

Parameter	Required	Type	Description
`trunk_name`	Yes	String	Alphanumeric + underscores only, max 16 chars
`nso_code`	Yes	String	Use `"ANY-ANY"`
`domain_name`	Yes	String	`{account_sid}.pstn.exotel.com`

Example request

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" -X POST \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks" \
  -H "Content-Type: application/json" \
  -d '{
    "trunk_name": "outbound_trunk",
    "nso_code": "ANY-ANY",
    "domain_name": "'"$EXOTEL_ACCOUNT_SID"'.pstn.exotel.com"
  }'

Example response

{
  "request_id": "10a67da360d446378d5c2b66407b7f18",
  "method": "POST",
  "http_code": 200,
  "response": {
    "code": 200,
    "error_data": null,
    "status": "success",
    "data": {
      "trunk_sid": "trmum1f708622631150902801a1n",
      "trunk_name": "outbound_trunk",
      "status": "active",
      "domain_name": "ameyo5m.pstn.exotel.com",
      "auth_type": "IP-WHITELIST",
      "nso_code": "ANY-ANY",
      "phone_numbers": "/v2/accounts/ameyo5m/trunks/trmum1f708622631150902801a1n/phone-numbers",
      "whitelisted_ips": "/v2/accounts/ameyo5m/trunks/trmum1f708622631150902801a1n/whitelisted-ips",
      "destination_uris": "/v2/accounts/ameyo5m/trunks/trmum1f708622631150902801a1n/destination-uris",
      "credentials": "/v2/accounts/ameyo5m/trunks/trmum1f708622631150902801a1n/credentials"
    }
  }
}

note

Save response.data.trunk_sid. Nested resource URLs in the response already use hyphenated paths — reuse them as-is.

Try It

Map phone number

POST/v2/accounts/{account_sid}/trunks/{trunk_sid}/phone-numbers

Request parameters

Parameter	Required	Type	Description
`phone_number`	Yes	String	E.164 (`+919876543210`)
`mode`	No	String	`pstn` (default) or `flow` (StreamKit / Voice AI)

Example request

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" -X POST \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks/<trunk_sid>/phone-numbers" \
  -H "Content-Type: application/json" \
  -d '{
    "phone_number": "+919876543210",
    "mode": "pstn"
  }'

Example response (`data`)

{
  "id": "41512",
  "phone_number": "+919876543210",
  "trunk_sid": "trmum1f708622631150902801a1n",
  "mode": "pstn",
  "date_created": "2026-01-23T10:26:54Z",
  "date_updated": "2026-01-23T10:26:54Z"
}

note

Save numeric mapping id for update/delete. Do not pass the E.164 string as the path id.

Try It

Map ACL (whitelisted IP) — outbound

POST/v2/accounts/{account_sid}/trunks/{trunk_sid}/whitelisted-ips

Request parameters

Parameter	Required	Type	Description
`ip`	Yes	String	Public IPv4
`mask`	No	Integer	CIDR mask (default `32`)

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" -X POST \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks/<trunk_sid>/whitelisted-ips" \
  -H "Content-Type: application/json" \
  -d '{ "ip": "44.248.146.11", "mask": 32 }'

Try It

Create SIP digest credentials — outbound

POST/v2/accounts/{account_sid}/trunks/{trunk_sid}/credentials

Request parameters

Parameter	Required	Type	Description
`user_name`	Yes	String	SIP digest username
`password`	Yes	String	Strong password
`friendly_name`	No	String	Label, max 32 chars

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" -X POST \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks/<trunk_sid>/credentials" \
  -H "Content-Type: application/json" \
  -d '{
    "user_name": "SIP_USER",
    "password": "strong_password_here",
    "friendly_name": "voice_ai_prod"
  }'

Try It

Scenario	Auth
Fixed-IP PBX / SBC	`whitelisted-ips`
Dynamic cloud egress	`credentials`
High security	Both

Map destination URI — inbound

POST/v2/accounts/{account_sid}/trunks/{trunk_sid}/destination-uris

Request parameters

Parameter	Required	Type	Description
`destinations`	Yes	Array	List of destination objects
`destinations[].destination`	Yes	String	`<ip_or_fqdn>:<port>;transport=tls` or `tcp`

Prefer TLS on port 5061.

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" -X POST \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks/<trunk_sid>/destination-uris" \
  -H "Content-Type: application/json" \
  -d '{
    "destinations": [
      { "destination": "44.248.146.11:5061;transport=tls" }
    ]
  }'

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" -X POST \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks/<trunk_sid>/destination-uris" \
  -H "Content-Type: application/json" \
  -d '{
    "destinations": [
      { "destination": "sip.yourcompany.com:5061;transport=tls" }
    ]
  }'

Save destination id from response.data for update/delete. Inbound Connect applet: Connect Applet inbound.

Try It

Manage & view APIs

List trunks

GET/v2/accounts/{account_sid}/trunks

Query parameters

Parameter	Required	Type	Description
`page_size`	No	Integer	Default `50`
`offset`	No	Integer	Default `0`
`trunk_sid`	No	String	Filter to one trunk

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks?page_size=50&offset=0"

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks?trunk_sid=<trunk_sid>"

Try It

Update trunk

PUT/v2/accounts/{account_sid}/trunks/{trunk_sid}

Request parameters

Parameter	Required	Type	Description
`trunk_name`	No	String	Max 16 chars, alphanumeric + underscores
`auth_type`	No	String	e.g. IP whitelist
`nso_code`	No	String	Use `"ANY-ANY"`

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" -X PUT \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks/<trunk_sid>" \
  -H "Content-Type: application/json" \
  -d '{ "trunk_name": "my_pbx_trunk" }'

Try It

Delete trunk

DELETE/v2/accounts/{account_sid}/trunks?trunk_sid={trunk_sid}

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" -X DELETE \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks?trunk_sid=<trunk_sid>"

warning

Irreversible. Removes phone mappings, ACLs, destination URIs, and credentials on the trunk.

Try It

List phone numbers

GET/v2/accounts/{account_sid}/trunks/{trunk_sid}/phone-numbers

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks/<trunk_sid>/phone-numbers"

Try It

Update phone number mode

PUT/v2/accounts/{account_sid}/trunks/{trunk_sid}/phone-numbers/{phone_number_id}

Request parameters

Parameter	Required	Type	Description
`phone_number`	Yes	String	E.164 — must match the mapping
`mode`	Yes	String	`pstn` or `flow`

phone_number_id is the numeric mapping id (e.g. 41523).

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" -X PUT \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks/<trunk_sid>/phone-numbers/41523" \
  -H "Content-Type: application/json" \
  -d '{
    "phone_number": "+919876543210",
    "mode": "flow"
  }'

Try It

Delete phone number mapping

DELETE/v2/accounts/{account_sid}/trunks/{trunk_sid}/phone-numbers?id={phone_number_id}

Id is a query parameter (?id=), not a path segment.

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" -X DELETE \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks/<trunk_sid>/phone-numbers?id=41523"

Try It

Trunk map lookup (Exophone → trunk)

GET/v2/accounts/{account_sid}/trunk-maps

Query parameters

Parameter	Required	Type	Description
`exophone`	Yes	String	DID in E.164
`trunk_sid`	No	String	Optional filter

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunk-maps?exophone=%2B919876543210"

{
  "exophone": "+919876543210",
  "trunk_sid": "trmum1f708622631150902801a1n",
  "phone_number_id": "41512",
  "mode": "pstn"
}

Try It

List ACLs

GET/v2/accounts/{account_sid}/trunks/{trunk_sid}/whitelisted-ips

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks/<trunk_sid>/whitelisted-ips"

Try It

Update whitelisted IP

PUT/v2/accounts/{account_sid}/trunks/{trunk_sid}/whitelisted-ips/{whitelist_entry_id}

Request parameters

Parameter	Required	Type	Description
`ip`	Yes	String	IPv4
`mask`	Yes	Integer	CIDR mask

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" -X PUT \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks/<trunk_sid>/whitelisted-ips/1153" \
  -H "Content-Type: application/json" \
  -d '{ "ip": "44.248.146.11", "mask": 32 }'

Try It

Delete whitelisted IP

DELETE/v2/accounts/{account_sid}/trunks/{trunk_sid}/whitelisted-ips?id={whitelist_entry_id}

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" -X DELETE \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks/<trunk_sid>/whitelisted-ips?id=1153"

Try It

List destination URIs

GET/v2/accounts/{account_sid}/trunks/{trunk_sid}/destination-uris

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks/<trunk_sid>/destination-uris"

Try It

Update destination URI

PUT/v2/accounts/{account_sid}/trunks/{trunk_sid}/destination-uris/{destination_id}

Request parameters

Parameter	Required	Type	Description
`priority`	No	Integer	Lower = higher priority (default `0`)
`weight`	No	Integer	Higher = more traffic (default `1`)

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" -X PUT \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks/<trunk_sid>/destination-uris/2543" \
  -H "Content-Type: application/json" \
  -d '{ "priority": 0, "weight": 5 }'

Try It

Delete destination URI

DELETE/v2/accounts/{account_sid}/trunks/{trunk_sid}/destination-uris?id={destination_id}

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" -X DELETE \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks/<trunk_sid>/destination-uris?id=2543"

Try It

List credentials

GET/v2/accounts/{account_sid}/trunks/{trunk_sid}/credentials

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks/<trunk_sid>/credentials"

Try It

Update SIP credential

PUT/v2/accounts/{account_sid}/trunks/{trunk_sid}/credentials/{credential_id}

Request parameters

Parameter	Required	Type	Description
`user_name`	No	String	New digest username
`password`	No	String	New password
`friendly_name`	No	String	Label, max 32 chars

Credential id is in the path. Delete uses ?id= instead.

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" -X PUT \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks/<trunk_sid>/credentials/1234" \
  -H "Content-Type: application/json" \
  -d '{
    "friendly_name": "voice_ai_prod",
    "password": "replace_with_strong_password"
  }'

Try It

Delete credential

DELETE/v2/accounts/{account_sid}/trunks/{trunk_sid}/credentials?id={credential_id}

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" -X DELETE \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks/<trunk_sid>/credentials?id=1234"

Try It

List trunk settings

GET/v2/accounts/{account_sid}/trunks/{trunk_sid}/settings

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks/<trunk_sid>/settings"

Try It

Set trunk alias (caller ID)

POST/v2/accounts/{account_sid}/trunks/{trunk_sid}/settings

Request parameters

Parameter	Required	Type	Description
`settings`	Yes	Array	Setting objects
`settings[].name`	Yes	String	Use `trunk_external_alias`
`settings[].value`	Yes	String	Caller ID in E.164

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" -X POST \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks/<trunk_sid>/settings" \
  -H "Content-Type: application/json" \
  -d '{
    "settings": [
      { "name": "trunk_external_alias", "value": "+919876543210" }
    ]
  }'

Try It

Delete trunk setting

DELETE/v2/accounts/{account_sid}/trunks/{trunk_sid}/settings?name={setting_name}

curl -s -u "$EXOTEL_API_KEY:$EXOTEL_API_TOKEN" -X DELETE \
  "https://$EXOTEL_SUBDOMAIN/v2/accounts/$EXOTEL_ACCOUNT_SID/trunks/<trunk_sid>/settings?name=trunk_external_alias"

Try It

Network & errors

SIP Trunking quickstart
Call directions
Connect Applet inbound
StreamKit SIP setup
Transport how-tos: SIP Trunk Configuration

Base URL and authentication​

Response envelope​

Workflow​

Endpoint index​

Setup​

Manage & view​

Setup APIs​

Create trunk​

Request parameters​

Example request​

Example response​

Try It​

Map phone number​

Request parameters​

Example request​

Example response (data)​

Try It​

Map ACL (whitelisted IP) — outbound​

Request parameters​

Try It​

Create SIP digest credentials — outbound​

Request parameters​

Try It​

Map destination URI — inbound​

Request parameters​

Try It​

Manage & view APIs​

List trunks​

Query parameters​

Try It​

Update trunk​

Request parameters​

Try It​

Delete trunk​

Try It​

List phone numbers​

Try It​

Update phone number mode​

Request parameters​

Try It​

Delete phone number mapping​

Try It​

Trunk map lookup (Exophone → trunk)​

Query parameters​

Try It​

List ACLs​

Try It​

Update whitelisted IP​

Request parameters​

Try It​

Delete whitelisted IP​

Try It​

List destination URIs​

Try It​

Update destination URI​

Request parameters​

Try It​

Delete destination URI​

Try It​

List credentials​

Try It​

Update SIP credential​

Request parameters​

Try It​

Delete credential​

Try It​

List trunk settings​

Try It​

Set trunk alias (caller ID)​

Request parameters​

Try It​

Delete trunk setting​

Try It​

Network & errors​

Related​

Base URL and authentication

Response envelope

Workflow

Endpoint index

Setup

Manage & view

Setup APIs

Create trunk

Request parameters

Example request

Example response

Try It

Map phone number

Request parameters

Example request

Example response (`data`)

Try It

Map ACL (whitelisted IP) — outbound

Request parameters

Try It

Create SIP digest credentials — outbound

Request parameters

Try It

Map destination URI — inbound

Request parameters

Try It

Manage & view APIs

List trunks

Query parameters

Try It

Update trunk

Request parameters

Try It

Delete trunk

Try It

List phone numbers

Try It

Update phone number mode

Request parameters

Try It

Delete phone number mapping

Try It

Trunk map lookup (Exophone → trunk)

Query parameters

Try It

List ACLs

Try It

Update whitelisted IP

Request parameters

Try It

Delete whitelisted IP

Try It

List destination URIs

Try It

Update destination URI

Request parameters

Try It

Delete destination URI

Try It

List credentials

Try It

Update SIP credential

Request parameters

Try It

Delete credential

Try It

List trunk settings

Try It

Set trunk alias (caller ID)

Request parameters

Try It

Delete trunk setting

Try It

Network & errors

Related