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CompaniesKlaviyoIncidents

Klaviyo: API 503 Errors

MinorStatus: resolvedStarted Resolved (47 min)3 updatesstspg.io (opens in new tab)

Affected components: Klaviyo APIServer-side

Timeline of updates

  1. identified

    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.

  2. monitoring

    We successfully implemented a fix as of 3:20 AM US/Eastern that restored all API activity. We are continuing to monitor the results.

  3. resolved

    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.

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Impact, status and times are the vendor’s own, as last archived. View on stspg.io (opens in new tab).

Cite this

Status incident (vendor impact label: minor) posted by Klaviyo, started 2026-04-26 07:24 UTC, resolved after 47 min, 3 update(s).

Title
API 503 Errors
Vendor
Klaviyo
Date
URL
https://rewindex.com/company/klaviyo/incidents/pcfm8kkzbmkl

Klaviyo profileRecent Klaviyo incidentsAll outages on April 26, 2026Klaviyo in April 2026MarkdownJSON