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As part of the Conversations API, this method's required scopes depend on the type of channel-like object you're working with. A corresponding channels: scope is required when working with public channels, groups: for private channels, also the same rules are applied for im: and mpim:.

This Conversations API method joins a user to an existing conversation.


Argument Example Required Description
token xxxx-xxxxxxxxx-xxxx Required

Authentication token bearing required scopes.

channel C1234567890 Required

ID of conversation to join

This method supports application/json via HTTP POST. Present your token in your request's Authorization header. Learn more.


If successful, the command returns a conversatoin object. If the calling token has already joined, it'll warn you about it too.

Typical success response

    "ok": true,
    "channel": {
        "id": "C061EG9SL",
        "name": "general",
        "is_channel": true,
        "is_group": false,
        "is_im": false,
        "created": 1449252889,
        "creator": "U061F7AUR",
        "is_archived": false,
        "is_general": true,
        "unlinked": 0,
        "name_normalized": "general",
        "is_shared": false,
        "is_ext_shared": false,
        "is_org_shared": false,
        "pending_shared": [],
        "is_pending_ext_shared": false,
        "is_member": true,
        "is_private": false,
        "is_mpim": false,
        "topic": {
            "value": "Which widget do you worry about?",
            "creator": "",
            "last_set": 0
        "purpose": {
            "value": "For widget discussion",
            "creator": "",
            "last_set": 0
        "previous_names": []
    "warning": "already_in_channel",
    "response_metadata": {
        "warnings": [

Typical error response if the conversation is archived and cannot be joined

    "ok": false,
    "error": "is_archived"


This table lists the expected errors that this method could return. However, other errors can be returned in the case where the service is down or other unexpected factors affect processing. Callers should always check the value of the ok params in the response.

Error Description

Value passed for channel was invalid.


Channel has been archived.


This type of conversation cannot be used with this method.


The calling token is not granted the necessary scopes to complete this operation.


No authentication token provided.


Some aspect of authentication cannot be validated. Either the provided token is invalid or the request originates from an IP address disallowed from making the request.


Authentication token is for a deleted user or workspace.


Authentication token is for a deleted user or workspace or the app has been removed.


The workspace token used in this request does not have the permissions necessary to complete the request.


This method cannot be called by a bot user.


This method cannot be called by a restricted user or single channel guest.


The method was passed an argument whose name falls outside the bounds of accepted or expected values. This includes very long names and names with non-alphanumeric characters other than _. If you get this error, it is typically an indication that you have made a very malformed API call.


The method was passed a PHP-style array argument (e.g. with a name like foo[7]). These are never valid with the Slack API.


The method was called via a POST request, but the charset specified in the Content-Type header was invalid. Valid charset names are: utf-8 iso-8859-1.


The method was called via a POST request with Content-Type application/x-www-form-urlencoded or multipart/form-data, but the form data was either missing or syntactically invalid.


The method was called via a POST request, but the specified Content-Type was invalid. Valid types are: application/x-www-form-urlencoded multipart/form-data text/plain.


The method was called via a POST request and included a data payload, but the request did not include a Content-Type header.


The workspace associated with your request is currently undergoing migration to an Enterprise Organization. Web API and other platform operations will be intermittently unavailable until the transition is complete.


The method was called via a POST request, but the POST data was either missing or truncated.


The server could not complete your operation(s) without encountering a catastrophic error. It's possible some aspect of the operation succeeded before the error was raised.


This table lists the expected warnings that this method will return. However, other warnings can be returned in the case where the service is experiencing unexpected trouble.

Warning Description

The method was called via a POST request, and recommended practice for the specified Content-Type is to include a charset parameter. However, no charset was present. Specifically, non-form-data content types (e.g. text/plain) are the ones for which charset is recommended.


The method was called via a POST request, and the specified Content-Type is not defined to understand the charset parameter. However, charset was in fact present. Specifically, form-data content types (e.g. multipart/form-data) are the ones for which charset is superfluous.

Argument Value
token Required Generate tokens to test with here.
channel Required
Extra args