Klaviyo experienced a minor incident on May 19, 2026 affecting SMS Sending - Toll Free Number SMS and SMS Sending - Toll Free Number MMS and 1 more component, lasting 3h 54m. The incident has been resolved; the full update timeline is below.
Affected components
Update timeline
- investigating May 19, 2026, 08:36 PM UTC
SMS event processing is delayed by approximately 2–3 hours. SMS sending is not impacted and recipients are receiving messages at the expected send times. This is impacting when SMS-related events appear in customer accounts, which may cause a delay in SMS event-triggered flows, real-time segments built on SMS event data, and reporting. Our team is actively investigating and we'll provide updates as soon as more information is available.
- identified May 19, 2026, 10:21 PM UTC
We have identified the cause of the issue and SMS event processing is recovering. Delays in processing SMS events are currently around 3 hours and continue to decrease. SMS campaign sending continues to be unaffected and recipients are continuing to receive messages at the expected send times. Customers may continue to see downstream delay in SMS event-triggered flow sending, real-time segments built on SMS event data, and reporting until processing has fully caught up. Customers may also encounter errors when creating and registering RCS agents, and when viewing videos within the platform. We'll provide updates as soon as more information is available.
- resolved May 20, 2026, 12:30 AM UTC
SMS events have been restored to real time processing as of 6:38 PM ET on May 19, 2026. Our Engineering team has monitored performance and see that systems have fully recovered. This incident has been resolved.