Klaviyo experienced a minor incident on September 21, 2026 affecting Email Sending and Processing and 1 more component, lasting 2h 2m. The incident has been resolved; the full update timeline is below.
Affected components
Update timeline
- investigating Sep 21, 2026, 03:56 PM UTC
We are investigating reports of delays affecting flow message sending. Some customers may see flow messages send later than expected. We will share another update as soon as we have more information.
- investigating Sep 21, 2026, 03:56 PM UTC
We are continuing to investigate this issue.
- identified Sep 21, 2026, 04:26 PM UTC
We have identified the cause of the delays affecting flow message sending and are working on a fix. Some customers may continue to see flow messages send later than expected while we resolve this. We will share another update shortly.
- monitoring Sep 21, 2026, 04:42 PM UTC
Flow message sending is recovering, and delays are clearing. Some customers may still see flow messages send later than expected as remaining processing catches up. We continue to monitor closely and appreciate your patience throughout this incident.
- monitoring Sep 21, 2026, 05:43 PM UTC
Delays have now largely cleared but some customers may still see flow messages send later than expected. We continue to monitor closely and will share another update shortly.
- resolved Sep 21, 2026, 05:58 PM UTC
Flow message sending has fully recovered and is processing at normal speeds. Delayed messages were not lost and have since been delivered. This incident has been resolved.