Klaviyo experienced a major incident on January 12, 2026 affecting Campaign Email Sending and SMS Sending - Other and 1 more component, lasting 1h 10m. The incident has been resolved; the full update timeline is below.
Affected components
Update timeline
- investigating Jan 12, 2026, 11:12 AM UTC
Beginning around 5am US Eastern time, we began observing delays in campaign scheduling and sending. New campaigns, and scheduled RAST (calculate Recipient at Send Times) campaigns, are unable to send. However non-RAST campaigns that were scheduled prior to 5am US Eastern Time are processing as usual. We do not expect data loss. We are actively working to resolve the incident and will provide updates as soon as possible.
- identified Jan 12, 2026, 11:51 AM UTC
As of 6:45am US Eastern, the issue has been identified and a fix implemented. Any new scheduled or sent campaigns should process, with slight delays. We are actively replaying any campaigns that were delayed.
- monitoring Jan 12, 2026, 12:05 PM UTC
A fix has been implemented and we are monitoring results. Campaign sending and scheduling is back to normal, and all delayed campaigns have been replayed.
- resolved Jan 12, 2026, 12:23 PM UTC
This incident has been resolved.