Dear X Developer Community,

We are announcing an important update to the X API effective today, February 18, 2025, that impacts the affiliation.user_id field in API responses.

What’s Changing?

Previously, the affiliation.user_id field returned a single user_id as a string even if a user had multiple affiliations. For example:

JSONCopied
{
  "data": {
    "affiliation": {
      "user_id": "1072254151508275200"
    }
  }
}

Now, the field returns an array of user_id values to accurately represent all of a user’s affiliations. The updated response is as follows:

JSONCopied
{
  "data": {
    "affiliation": {
      "user_id": [
        "1072254151508275200",
        "1815006710651551745"
      ]
    }
  }
}

This change provides a more complete dataset by acknowledging multiple affiliations.

Who Is Impacted?

This update affects developers making API requests with the parameter:

• user.fields=affiliation

If your application currently assumes that affiliation.user_id is a single string, please update your code to handle the array format.

We apologize for the short notice and appreciate your adaptability as we work to enhance the X API. Thank you for your continued support and partnership.

Best regards,

X Developer Platform Team