Create SMS block for user

POST

/domains/{domain}/users/{user}/smsblocks

Last modified:2026-10-07 23:44:16

OperationId:CreateSmsBlockForUser

Adds an SMS opt-out, so blocked-number can no longer send SMS or MMS to requesting-number. Requires Reseller or Super User scope. A Reseller reaches the domains in its territory.

An SMS block is an opt-out: an off-net number texted STOP to one of your numbers. The platform adds the block on STOP and sets it inactive on START. While it is active, an SMS or MMS from blocked-number to requesting-number is refused. Use this to record an opt-out that reached you another way. The block is created active, and both numbers are normalized: spaces and punctuation are removed, and a 10-digit number gets +1. Adding a pair that was set inactive makes it active again.

Below Super User, the block must name a domain, and blocked-number must be an SMS number of that domain. A block applies wherever blocked-number is used, so a block on another tenant's number, or one without a domain, is Super User only.

The change is applied at once.

This is the same create as POST /domains/{domain}/smsblocks: the user in the path is not stored on the block.

Request

Authorization

Bearer Token

Provide your bearer token in the

Authorization

header when making requests to protected resources.

Example:

Authorization: Bearer ********************

Path Params

Body Params application/jsonRequired

Examples

Responses

🟢202Accepted

application/json

The block is created and already applied.

Bodyapplication/json

🟠400Bad Request

🟠401Unauthorized

🟠403Forbidden

🟠404Not Found

🟠409Conflict

🔴500Internal Server Error

🟠420Rate Limit Exceeded

Request Example

Shell

JavaScript

Java

Swift

cURL

Block a numberTen-digit numbers

curl --location 'https://awqacore01.crexendocloud.com/ns-api/v2/domains/example.com/users/1001/smsblocks' \
--header 'Authorization: Bearer <token>' \
--header 'Content-Type: application/json' \
--data '{
    "requesting-number": "+15555550142",
    "blocked-number": "+15555550100"
}'

Response Example

202 - Block a number

{
    "code": 202,
    "message": "Accepted"
}

Modified at 2026-10-07 23:44:16

Read SMS block

List message sessions in domain