Klaviyo experienced a 14.9-hour incident in which outbound event webhooks were significantly delayed for customers and third-party connected apps. To aid recovery, Klaviyo paused new webhook processing at 5:11 PM ET on October 22, 2026, with processing resuming at 11:28 PM ET the same night. The backlog was fully cleared and webhook delivery restored by 2:40 AM ET on October 23, 2026, with all webhook data retained throughout; flow-based webhook actions were unaffected.
Trusted by 1,000+ teams
Stop finding out about outages from your users. Monitor 6,320+ cloud services and get alerted the second something breaks.
Event webhook delivery was fully restored at 2:40 AM US/Eastern on October 23, 2026 after the backlog was processed. Webhook data was retained, and webhook actions in flows were not affected. We apologize for the disruption this caused. This incident has been resolved.
New event webhooks are being delivered again after processing resumed at 11:28 PM US/Eastern on October 22, 2026. Some customers and third-party apps connected to Klaviyo accounts may continue to see delays while the backlog is processed, and we expect these delays to decrease over time. Webhook data has been retained, and webhook actions in flows are not affected at this time. We continue to monitor closely and appreciate your patience throughout this incident.
Some customers and third-party apps connected to Klaviyo accounts are experiencing delays receiving event webhooks. Webhook actions in flows are not affected at this time. To support recovery, we temporarily paused processing of new webhooks at 5:11 PM US/Eastern on October 22, 2026, and earlier webhooks are still being delivered with delays. Webhook data is being retained, and we expect delayed and paused webhooks to be delivered once processing resumes. We are working to resolve this as quickly as possible and will share another update shortly.
With IsDown, you can monitor all your critical services' official status pages from one centralized dashboard and receive instant alerts the moment an outage is detected. Say goodbye to constantly checking multiple sites for updates and stay ahead of outages with IsDown.
Start free trialNo credit card required · Cancel anytime · 6320 services available
Integrations with