Outage report · Partial outage

Slack outage on May 8, 2026

Incident: Scheduled Grid Migrations are experiencing extended downtime

SeverityPartial outage

StartedMay 8, 2026, 12:13UTC

ResolvedMay 8, 2026, 17:44UTC

Duration5h 31m

What happened

Slack reported a partial outage starting May 8, 2026, 12:13 UTC. It was marked resolved at May 8, 2026, 17:44 UTC.

The incident lasted 5h 31m from first report to resolution.
Slack had reported no other partial or major outages in the 90 days before it.
9 other vendors we track reported a significant incident within 12 hours of it.

Latest update from Slack

5:13am PDT Users who are undergoing scheduled Grid Migrations are experiencing extended downtime. Downtime is expected during a Grid Migration however it's taking longer than usual. During the downtime users are unable to access Slack until the migration completes. We've identified an issue with Job Queues, which may be the cause and are investigating this further. The next update will be provided once additional information becomes available.  10:44am PDT This issue is now resolved.Current status and actions being taken: We identified database write throttling as the cause of the stalled grid migrations. We applied a drop rule for jobs that were stuck in a retry loop, which has restored normal migration processing. Scope: A small number of enterprise users undergoing grid migrations experienced extended delays in accessing Slack. Current impact to end users: Affected users may have experienced an inability to access Slack during their migration window. Known workar

Read Slack's official incident report ↗