Outage in Klaviyo
API 503 Errors
Resolved MinorIncident Report
Summary AI Generated
Klaviyo experienced intermittent API errors starting at 2:27 AM US/Eastern on 04/25/2026, causing customers to encounter 503 errors when logging in, loading pages, or making API requests. The engineering team identified the root cause and implemented a fix at 3:20 AM US/Eastern that restored all API functionality. The incident was fully resolved after 50 minutes, with customers needing to retry any requests that failed during the outage window.
Starting at approximately 2:27 AM US/Eastern on 04/25/2026, we began experiencing intermittent elevated errors across our APIs. Some customers may experience 503 errors when trying to log into Klaviyo, load certain pages or make API requests. Our Engineering Team has identified the root cause and has implemented mitigations. We'll provide updates as soon as more information is available.
Components affected
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Latest Updates ( sorted recent to last )
RESOLVED
4 days ago - at 04/26/2026 08:11AM
We confirmed that all API activity has been stable since the fix was released. Any requests that returned 503 errors during the outage window will need to be retried. This incident has been resolved.
MONITORING
4 days ago - at 04/26/2026 07:43AM
We successfully implemented a fix as of 3:20 AM US/Eastern that restored all API activity. We are continuing to monitor the results.
IDENTIFIED
4 days ago - at 04/26/2026 07:24AM
Starting at approximately 2:27 AM US/Eastern on 04/25/2026, we began experiencing intermittent elevated errors across our APIs. Some customers may experience 503 errors when trying to log into Klaviyo, load certain pages or make API requests. Our Engineering Team has identified the root cause and has implemented mitigations. We'll provide updates as soon as more information is available.
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