Unassign Number from Trunk

DELETE

api

Account

{auth_id}

numbers

{phone_number}

assign

Unassign Number from Trunk

curl --request DELETE \
  --url https://api.vobiz.ai/api/v1/Account/{auth_id}/numbers/{phone_number}/assign \
  --header 'X-Auth-ID: <api-key>' \
  --header 'X-Auth-Token: <api-key>'

import requests

url = "https://api.vobiz.ai/api/v1/Account/{auth_id}/numbers/{phone_number}/assign"

headers = {
    "X-Auth-ID": "<api-key>",
    "X-Auth-Token": "<api-key>"
}

response = requests.delete(url, headers=headers)

print(response.text)

const options = {
  method: 'DELETE',
  headers: {'X-Auth-ID': '<api-key>', 'X-Auth-Token': '<api-key>'}
};

fetch('https://api.vobiz.ai/api/v1/Account/{auth_id}/numbers/{phone_number}/assign', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

{
  "api_id": "<string>",
  "error": "<string>",
  "message": "<string>"
}

{
  "api_id": "<string>",
  "error": "<string>",
  "message": "<string>"
}

DELETE https://api.vobiz.ai/api/v1/Account/{auth_id}/numbers/{phone_number}/assign

Use this endpoint to remove the assignment between a phone number and a SIP trunk. After unassignment, the number remains in your account inventory but no longer routes calls through the previously assigned trunk.

Authentication required:

X-Auth-ID - Your account Auth ID
X-Auth-Token - Your account Auth Token
Content-Type: application/json

Warning: Unassigning a number from a trunk immediately stops routing inbound calls to that number. Ensure you have an alternative routing configuration, or reassign the number to a different trunk if you want to continue receiving calls.

URL Encoding Notice: Always encode the phone number in the URL. Use %2B instead of the + symbol. For example: %2B912271264217 (not +912271264217). Failure to encode properly may result in a 404 error.

Note: This endpoint uses the DELETE HTTP method on the same URL path as the assignment endpoint. No request body is required.

URL Parameters

Field	Type	Required	Description
`auth_id`	string	Yes	Your unique Vobiz account identifier (e.g., `MA_XXXXXXXX`). Must match your `X-Auth-ID` header.
`PHONE_NUMBER`	string	Yes	Phone number to unassign, URL-encoded. Use `%2B` instead of `+` (e.g., `%2B912271264217`).

No Request Body Required: The DELETE method does not require a request body. The phone number specified in the URL will be unassigned from its currently associated trunk.

Examples

curl -X DELETE "https://api.vobiz.ai/api/v1/Account/{auth_id}/numbers/%2B1234567890/assign" \
  -H "X-Auth-ID: {auth_id}" \
  -H "X-Auth-Token: {auth_token}" \
  -H "Content-Type: application/json"

curl -X DELETE "https://api.vobiz.ai/api/v1/Account/{auth_id}/numbers/{phone_number}/assign" \
  -H "X-Auth-ID: {auth_id}" \
  -H "X-Auth-Token: {auth_token}" \
  -H "Content-Type: application/json"

Response

On successful unassignment, the API returns 204 No Content with no response body.

Success Response - 204 No Content

HTTP/1.1 204 No Content
Date: Thu, 23 Jan 2026 07:07:24 GMT
Server: Vobiz API Gateway

Verifying the Unassignment

After unassignment, you can confirm the change by listing numbers (the trunk_group_id will be absent) and by retrieving the trunk to confirm it no longer references this number.

Number after unassign (from list-numbers)

{
  "id": "aabbccdd-1234-5678-90ab-cdef12345680",
  "account_id": "MA_XXXXXXXX",
  "e164": "+919876543210",
  "country": "IN",
  "region": "Karnataka",
  "capabilities": {
    "voice": true,
    "sms": false,
    "mms": false,
    "fax": false
  },
  "status": "active",
  "provider": "",
  "setup_fee": 100,
  "monthly_fee": 300,
  "currency": "INR",
  "voice_enabled": true,
  "tags": [],
  "purchased_at": "2026-05-01T06:58:38.796024Z",
  "is_blocked": false,
  "created_at": "2026-03-31T18:30:00Z",
  "updated_at": "2026-05-12T07:07:24.000000Z",
  "is_trial_number": false,
  "last_billing_date": "2026-05-01T06:58:38.796024Z",
  "next_billing_date": "2026-06-01T06:58:38.796024Z",
  "minimum_commitment_months": 0,
  "aadhaar_verification_required": false,
  "aadhaar_verified": false,
  "source": "purchased"
}

Trunk after unassign (from retrieve-trunk)

{
  "trunk_id": "aabbccdd-1234-5678-90ab-cdef12345678",
  "account_id": "MA_XXXXXXXX",
  "name": "Acme Production Trunk",
  "trunk_domain": "aabbccdd-1234-5678-90ab-cdef12345678.sip.vobiz.ai",
  "trunk_status": "active",
  "secure": false,
  "trunk_direction": "inbound",
  "concurrent_calls_limit": 10,
  "cps_limit": 2,
  "primary_uri_uuid": "aabbccdd-1234-5678-90ab-cdef12345681",
  "description": "",
  "inbound_destination": "aabbccdd-1234-5678-90ab-cdef12345681",
  "transport": "udp",
  "recording": true,
  "enable_transcription": true,
  "pii_redaction": false,
  "webhook_method": "POST",
  "recording_webhook_enabled": false,
  "created_at": "2026-04-17T10:28:06.112095Z",
  "updated_at": "2026-05-12T07:07:24.000000Z"
}

Error Responses

Error Response - 404 Not Found (Invalid Phone Number)

{
  "error": "Number not found",
  "message": "The phone number could not be found or is not assigned to any trunk."
}

Error Response - 400 Bad Request (Invalid Format)

{
  "error": "invalid request",
  "message": "The phone number format is invalid. Ensure it is URL-encoded correctly."
}

Quick Tips:

Success Code: Look for 204 No Content response
URL Encoding: Always use %2B instead of + in the phone number
No Request Body: DELETE requests do not require a request body
Number Format: Use E.164 format with country code (e.g., +1234567890)

Important Considerations:

Immediate Effect: Unassignment takes effect immediately; inbound calls will no longer route
Number Retention: The number remains in your account inventory after unassignment
Reassignment: You can reassign the number to a different trunk or the same trunk later
Billing: Number rental charges continue until you release the number using the Unrent Number endpoint

Next Steps:

Reassign to a different trunk using the Assign Number endpoint
Or, release the number entirely using the Unrent Number endpoint
Verify the unassignment by listing your trunk details
Update your application logic to handle the routing change

Authorizations

X-Auth-ID

string

header

required

Your Vobiz account Auth ID

X-Auth-Token

string

header

required

Your Vobiz account Auth Token

Path Parameters

auth_id

string

required

Your account Auth ID

Example:

"MA_XXXXXX"

phone_number

string

required

The phone number to unassign, URL-encoded (use %2B instead of +).

Example:

"%2B912271264217"

Response

Number unassigned

Unassign Number from Trunk

curl --request DELETE \
  --url https://api.vobiz.ai/api/v1/Account/{auth_id}/numbers/{phone_number}/assign \
  --header 'X-Auth-ID: <api-key>' \
  --header 'X-Auth-Token: <api-key>'

import requests

url = "https://api.vobiz.ai/api/v1/Account/{auth_id}/numbers/{phone_number}/assign"

headers = {
    "X-Auth-ID": "<api-key>",
    "X-Auth-Token": "<api-key>"
}

response = requests.delete(url, headers=headers)

print(response.text)

const options = {
  method: 'DELETE',
  headers: {'X-Auth-ID': '<api-key>', 'X-Auth-Token': '<api-key>'}
};

fetch('https://api.vobiz.ai/api/v1/Account/{auth_id}/numbers/{phone_number}/assign', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

{
  "api_id": "<string>",
  "error": "<string>",
  "message": "<string>"
}

{
  "api_id": "<string>",
  "error": "<string>",
  "message": "<string>"
}

​URL Parameters

​Examples

​Response

​Verifying the Unassignment

​Error Responses

Authorizations

Path Parameters

Response

URL Parameters

Examples

Response

Verifying the Unassignment

Error Responses