Requiring subscriptions for RTM presence events beginning November 15, 2017

Published:Tuesday, October 3, 2017Updated:Tuesday, January 30, 2018

RTM API Presence is now only available via subscription. As of January 2018, presence_change events are not dispatched without presence subscriptions established with presence_sub. Relatedly, current user presence status is no longer communicated in rtm.start. Learn more.

Beginning November 15, 2017, the RTM API's presence_sub event will be available via presence subscription only.

Back in June, we introduced new ways to track user presence and the presence_change event in the RTM API.

Dispatching presence events for all users in a workspace is an expensive operation for Slack. A flood of presence events from large workspaces can also disrupt your app's ability to process more useful, timely messages.

By subscribing only to the presence events your app needs to provide presence-dependent functionality, you can reduce unnecessary websocket traffic.

What's changing?

Slack will stop automatically dispatching presence_change events over RTM websockets as user presence changes in a workspace.

To continue receiving presence_change events you must:

  1. Enable presence subscriptions for your RTM streams by passing the batch_presence_aware=1 argument to rtm.start or rtm.connect.
  2. Post presence_sub events to the websocket, noting which user IDs your app wants to track presence status for.
  3. Consume the users array attached to batched presence_change events, dispatched when presence changes for users your app is subscribed to.

In addition, rtm.start will no longer include user presence and online field information in its initial preamble JSON. You'll need to use users.getPresence to determine initial presence status instead.

What isn't changing?

Presence events are not currently issued as part of the Events API, therefore nothing is changing on the Events API.

What happens if I do nothing?

Your app will stop receiving presence_change events on any websockets your app is connected to beginning November 15, 2017. If your app uses those presence events to direct functionality, your app might not do what it's supposed to do without that information.

Your app will no longer receive the current state of presence and online information for workspace users when connecting via rtm.start.

When is this happening?

Presence subscriptions will become mandatory on November 15, 2017.

Please contact us if you have any concerns at