Klaviyo: Elevated errors for SMS opt-ins, scheduling, and sending

Impact: majorStatus: resolvedStarted 2026-07-21 20:36 UTCResolved 2026-07-21 21:09 UTC (33 min)4 updatesSource: stspg.io

Summary

Klaviyo reported a major incident affecting SMS subscriptions, delaying SMS sends, and causing errors creating or scheduling SMS and WhatsApp campaigns. It started at 2026-07-21 20:36 UTC and was resolved at 2026-07-21 21:09 UTC, lasting 32 min. Klaviyo implemented a fix but did not disclose the cause.

Machine-written from the archived incident (Sol). Check the timeline before relying on it.

Affected components: Campaigns - WhatsApp SendingWhatsApp SendingCampaigns - Text Message SendingText Message Sending

Timeline of updates

investigating2026-07-21 20:36 UTC
We are currently investigating an issue impacting SMS subscriptions, delays in SMS sending, and errors when creating or scheduling SMS and WhatsApp campaigns. We are working to restore normal service as quickly as possible. We will share another update as soon as we have more information.
identified2026-07-21 20:47 UTC
We have identified the cause of the issue and a fix has been implemented. We are starting to see improvements in system performance.
monitoring2026-07-21 20:57 UTC
System performance for SMS opt-in forms, sending, and campaign creation and scheduling remains stable. We continue to monitor closely and appreciate your patience throughout this incident.
resolved2026-07-21 21:09 UTC
SMS subscriptions, SMS sending, and the creation and scheduling of SMS and WhatsApp campaigns are operating as expected. This incident has been resolved.

Rewindex changes for this incident

Major incident: Elevated errors for SMS opt-ins, scheduling, and sending 2026-07-21 20:36 UTC

Impact, status and times are the vendor’s own, as last archived. View on stspg.io (opens in new tab). Klaviyo profile · Recent Klaviyo incidents · Markdown · JSON