Klaviyo change history: Widespread Access Outage

Klaviyo reported a critical outage affecting login, sending and other services, caused by an upstream provider outage. The incident started at 2025-10-20 08:58 UTC and lasted 32 h 7 min, disrupting access and delaying sending, segmentation, unsubscribes and conversion attribution analytics. All services were restored, with resolution recorded at 2025-10-21 17:06 UTC.