Slack incident

Users May Not Receive Notifications on Slack Thread Replies

Minor Resolved View vendor source →

Slack experienced a minor incident on April 27, 2026 affecting Notifications, lasting 3h 24m. The incident has been resolved; the full update timeline is below.

Started
Apr 27, 2026, 05:11 PM UTC
Resolved
Apr 27, 2026, 08:36 PM UTC
Duration
3h 24m
Detected by Pingoru
Apr 27, 2026, 05:11 PM UTC

Affected components

Notifications

Update timeline

  1. investigating Apr 27, 2026, 05:11 PM UTC

    Some users have reported issues with thread replies not generating a notification banner. We’re investigating the issue, and have identified a recent deployment as a possible trigger. We apologize for the inconvenience and will report back as more information becomes available.

  2. investigating Apr 27, 2026, 06:07 PM UTC

    We’re observing positive signals after rolling back the deployment in test environments. We will complete some final validations before rolling back the deployment in the production environment. Thank you for your patience as we work through this one. We’ll report back once production rollback is completed or if there are substantial updates to share.

  3. resolved Apr 27, 2026, 08:36 PM UTC

    We’ve successfully performed a rollback in the production environment, and all systems are now functioning as expected. Users should no longer experience any issues with thread replies not generating a notification banner. We apologize for any inconvenience and appreciate your patience.