Changes / Klaviyo / Issue with Time Delays in Flows
Klaviyo: Major incident: Issue with Time Delays in Flows
Summary
Klaviyo reported a major degradation starting 2026-08-27 00:09 UTC: some profiles stalled at flow time delays, affecting email, text messaging, push, and WhatsApp sending. Campaigns and flows without time delays were unaffected. A fix was deployed and affected-message processing completed; the incident resolved at 2026-08-27 03:42 UTC after 3 h 33 min.
Machine-written from the diff below (Sol; type: incident degradation). Check the diff before relying on it.
What changed
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After: Issue with Time Delays in Flows
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After: major
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After: resolved
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After: 2026-08-27 00:09 UTC
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After: 2026-08-27 03:42 UTC
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After: Email Sending, Flows - Email Sending, Flows - Mobile Push Sending, Flows - Processing, Flows - Text Message Sending, Flows - WhatsApp Sending, Mobile Push Sending, Processing, Text Message Sending, WhatsApp Sending
Before: not present
After: At 3:25 PM US/Eastern on August 26, 2026, we began experiencing an issue where some profiles are not progressing past time delay actions in flows as expected. This is affecting flow sending across all messaging channels, including email, text messaging, push, and WhatsApp. Message sending from campaigns, and flows that do not include time delay actions are not impacted.
We are actively working on a fix. We will continue to provide updates as more information becomes available.
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After: Our Engineering team has identified the cause of this issue and is working to implement a fix to resolve the remaining impact on sending for flows affected by the time delay issue. Once the fix is rolled out, we will review and repair any impacted flows.
We are working to resolve this as quickly as possible and will share another update shortly.
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After: As of 9:30PM US/Eastern, flows have resumed sending as expected across all affected messaging channels. We are processing the backlog of affected flow messages. A fix has been deployed and system performance is improving.
We continue to monitor closely and appreciate your patience throughout this incident.
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After: As of 11:26 PM US/Eastern on August 26, 2026, the repair to process affected flow messages from the window of impact has been completed, and flow sending has resumed as expected across all channels. We apologize for the disruption this caused. This incident has been resolved.
First version of this incident archived by Rewindex. View the live incident.
History of this incident
| When (UTC) | Change | Kind |
|---|---|---|
| Major incident: Issue with Time Delays in Flows (this change) Klaviyo reported a major degradation starting 2026-08-27 00:09 UTC: some profiles stalled at flow time delays, affecting email, text messaging, push, and WhatsApp sending. Campaigns and flows without time delays were unaffected. A fix was deployed and affected-message processing completed; the incident resolved at 2026-08-27 03:42 UTC after 3 h 33 min. | Major incident |