Klaviyo outage history

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.

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.

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.

We are investigating reports of delays affecting flow message sending. Some customers may see flow messages send later than expected. Immediate sends are not affected and are going out as expected. We will share another update as soon as we have more information.

We are continuing to investigate delays affecting some flow email sending. Immediate sends remain unaffected. We will share another update as soon as we have more information.

We have identified the cause of the delays affecting flow message sending and are working on a fix. Some customers may continue to see flow messages send later than expected while we resolve this. We will share another update shortly.

We are continuing to work on the fix for this issue. Some customers may continue to see flow emails send later than expected while we resolve this. Immediate sends remain unaffected. We will share another update shortly.

We are actively working to clear the delayed flow emails and restore normal flow email sending. Some customers may still see flow emails send later than expected while this work completes. Immediate sends remain unaffected. We will share another update shortly.

We are still working to clear the delayed flow execution, and flow sending has not yet returned to normal. Some customers may continue to see messages send later than expected while we complete this work. Immediate sends remain unaffected. We will share another update shortly.

We are continuing to work on the fix for this issue. Some customers may continue to experience delays in flow processing while we resolve this. Immediate sends remain unaffected. We will share another update shortly.

We are continuing to work on resolving the delays affecting flow processing. Some customers may continue to experience delays in their flows while we work through this. Immediate sends remain unaffected, and delayed messages remain queued while we work to process them. We will share another update shortly.

Flow processing has resumed and the delayed backlog is actively clearing. This incident affected all flow processing - including flow-triggered email, SMS, WhatsApp and push messages, as well as flow updates to profiles and lists. Some customers may continue to see delays until the backlog fully catches up. Immediate sends were not affected. We continue to monitor closely and appreciate your patience throughout this incident.

Delays have now largely cleared, though some customers may still see flow messages send later than expected. We continue to monitor closely and appreciate your patience throughout this incident.

Flow processing has returned to normal, and delayed flow actions - including email, SMS, and push messages, as well as profile and list updates - have fully caught up. Immediate sends were not affected. We apologize for the disruption this caused. This incident has been resolved.

All customers are experiencing delays of up to an hour in analytics events, so Sent and Delivered reporting and received profile events may temporarily appear missing. Campaign and flow sending, along with open and click events, are not affected. We have identified the cause of the delays. We are working to resolve this as quickly as possible and will share another update shortly.

Delays in analytics events have increased and now reach up to 1 hour and 45 minutes for all customers. Segments that rely on these events may not be up to date while our Engineering team actively processes the backlog. Campaign and flow sending, along with open and click events, remain unaffected. We are working to resolve this as quickly as possible and will share another update shortly.

Delays have now largely cleared. We continue to monitor closely and will share another update shortly.

As of 10:10 pm Eastern Time on Oct 8th, all delayed analytics have been processed and new analytics are processing in real time. This incident is now resolved.

We are investigating reports that some customers are unable to log in to Klaviyo or are seeing pages load slowly or not at all. Our team is actively working to restore normal access. We will share another update as soon as we have more information.

We are continuing to investigate issues preventing some customers from logging in to Klaviyo or loading pages in the app. We have not seen any impact to campaign or flow sending. We will share another update as soon as we have more information.

The issue has been identified and a fix is being implemented.

A fix has been deployed, and customers should now be able to log in to Klaviyo and load pages normally. If you were logged out during this incident, you may need to log in again. We continue to monitor closely and appreciate your patience throughout this incident.

Customers can now log in to Klaviyo and load pages normally, and the system remains stable. This incident has been resolved.

We are investigating reports of delays affecting flow message sending. Some customers may see flow messages send later than expected. We will share another update as soon as we have more information.

We are continuing to investigate this issue.

We have identified the cause of the delays affecting flow message sending and are working on a fix. Some customers may continue to see flow messages send later than expected while we resolve this. We will share another update shortly.

Flow message sending is recovering, and delays are clearing. Some customers may still see flow messages send later than expected as remaining processing catches up. We continue to monitor closely and appreciate your patience throughout this incident.

Delays have now largely cleared but some customers may still see flow messages send later than expected. We continue to monitor closely and will share another update shortly.

Flow message sending has fully recovered and is processing at normal speeds. Delayed messages were not lost and have since been delivered. This incident has been resolved.

We are investigating reports of delays affecting flow message sending. Some customers may see flow messages send later than expected. We will share another update as soon as we have more information.

We have identified the cause of the delays affecting flow message sending and are working on a fix. Some customers may continue to see flow messages send later than expected while we resolve this. We will share another update shortly.

We are seeing early signs of improvement and continue to work towards full recovery. Customers may still see flow messages send later than expected. We will share another update shortly.

Flow message sending is recovering, and delays are continuing to clear. Some customers may still see flow messages send later than expected as remaining processing catches up. We continue to monitor closely and appreciate your patience throughout this incident.

Flow message sending has fully recovered and is processing at normal speeds. Delayed messages were not lost and have since been delivered. This incident has been resolved.

We are currently investigating a delay in the sending of event-triggered flows. Some customers may see these flows send later than expected. Scheduled campaigns and other areas of Klaviyo are not affected. We will share another update as soon as we have more information.

We are continuing to investigate the delays affecting event-triggered flows. Some customers may see these flows send with delays of approximately 90 minutes while we work to restore normal performance. We will provide another update shortly.

We have identified the cause of the delays affecting event-triggered flows. Affected flows may see delays of approximately 2 hours. Our team is now working on a fix to restore processing back to normal speed. We are working to resolve this as quickly as possible and will share another update shortly.

Our team is continuing to implement a fix to mitigate the delays affecting event-triggered flows. Delays to affected flows remain at approximately 2 hours. We are working to resolve this as quickly as possible and will share another update shortly.

Event-triggered flow processing is recovering, and our systems are now working through the backlog of delayed messages. Delayed messages will continue to send automatically as the backlog clears. A fix has been deployed and system performance is improving. We continue to monitor closely and appreciate your patience throughout this incident.

The backlog of delayed event-triggered flows has been fully processed and all systems are now operating normally. We apologize for the disruption this caused. This incident has been resolved.

At 3:25 PM US/Eastern on August 26, 2026, we began experiencing an issue where some profiles are not progressing past time delay actions in flows as expected. This is affecting flow sending across all messaging channels, including email, text messaging, push, and WhatsApp. Message sending from campaigns, and flows that do not include time delay actions are not impacted. We are actively working on a fix. We will continue to provide updates as more information becomes available.

Our Engineering team has identified the cause of this issue and is working to implement a fix to resolve the remaining impact on sending for flows affected by the time delay issue. Once the fix is rolled out, we will review and repair any impacted flows. We are working to resolve this as quickly as possible and will share another update shortly.

As of 9:30PM US/Eastern, flows have resumed sending as expected across all affected messaging channels. We are processing the backlog of affected flow messages. A fix has been deployed and system performance is improving. We continue to monitor closely and appreciate your patience throughout this incident.

As of 11:26 PM US/Eastern on August 26, 2026, the repair to process affected flow messages from the window of impact has been completed, and flow sending has resumed as expected across all channels. We apologize for the disruption this caused. This incident has been resolved.

We are currently experiencing delays of up to approximately 3 hours in how quickly recent profile property updates are reflected in real-time segments. This means changes to profiles may take longer than usual to update segment membership, which can affect segment-based targeting. Email and SMS sending and other core functions are operating normally. We are actively working to resolve this and will share another update as soon as we have more information.

A fix has been deployed and system performance is improving. Recent profile property updates are now being reflected in real-time segments more quickly, and the delay has improved to approximately 2.5 hours. Changes to profiles may still take slightly longer than usual to update segment membership as the system continues to catch up. Email and SMS sending and other core functions remain unaffected. We continue to monitor closely and appreciate your patience throughout this incident.

Profile property updates are now being reflected in real-time segments at normal speed. Any profile property changes made during the incident window have been reflected in segment membership as expected, and no action is required on your part. This incident has been resolved.

Between 1:15 PM and 2:00 PM US/Eastern on August 12, 2026, some customers experienced errors when scheduling campaigns, and some scheduled campaigns were canceled. If you scheduled a campaign during this window, we recommend checking its status in your account. A fix has been deployed and system performance is improving. We continue to monitor closely and will confirm once fully resolved.

Campaign scheduling has returned to normal operation. If you scheduled a campaign between 1:15 PM and 2:00 PM US/Eastern on August 12, 2026, we recommend checking its status and rescheduling if needed. This incident has been resolved.

Beginning around 12:00 PM US/Eastern on August 5, 2026, we began investigating an issue affecting some email subscription and campaign features. Customers using double opt-in may find that new subscribers are not receiving confirmation emails as expected. Some users may encounter errors when sending preview emails, scheduling campaigns, or checking estimated recipient counts. Our team is working to resolve this. We will share another update as soon as we have more information.

We have identified the source of the issue affecting some email subscription and campaign features. Customers may continue to see errors when sending preview emails and customers using double opt-in may find that new subscribers are not receiving confirmation emails. Campaign scheduling has recovered and is working as expected. We are working to resolve this as quickly as possible and will share another update shortly.

A fix has been deployed and the affected email subscription and campaign features have recovered. Double opt-in confirmation emails are sending again, and preview emails and estimated recipient counts are working as expected. We continue to monitor closely and appreciate your patience throughout this incident.

The email subscription and campaign features affected by this incident remain stable and are operating normally. Double opt-in confirmation emails, preview emails, and estimated recipient counts have returned to normal operation. Confirmation emails that failed to send during the incident are being resent. This incident has been resolved.

Beginning around 8:09 AM US/Eastern on July 23, 2026, profile imports started through the API, CSV upload, or SFTP may fail to complete, and the imported profiles may not be created. New integrations connected during this period may also be delayed in starting their initial sync. We have identified the cause and are deploying a fix. We are working to resolve this as quickly as possible and will share another update shortly.

Profile imports have recovered, and imports through the API, CSV upload, or SFTP are processing normally again. Integrations connected during the impact window are also resuming their initial syncs. Our team is working to reprocess API imports that failed during the incident. We continue to monitor closely and appreciate your patience throughout this incident.

The system remains stable, and imports through the API, CSV upload, or SFTP are processing normally. Imports that failed during the incident were not reprocessed automatically. If an import you started between 8:00 AM and 11:00 AM US/Eastern on July 23, 2026 did not complete, please re-run it to ensure those profiles are imported. This incident has been resolved.

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.

We have identified the cause of the issue and a fix has been implemented. We are starting to see improvements in system performance.

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.

SMS subscriptions, SMS sending, and the creation and scheduling of SMS and WhatsApp campaigns are operating as expected. This incident has been resolved.

At 4:00 PM US/Eastern on July 8, 2026, we identified delays syncing product updates from integrations using webhooks. This is causing catalog data, including in Templates and the Customer Hub, to not update in real time. Customer may see product data being out of date by up to 4 hours. Sending is not impacted but the product data in templates may not reflect real-time information. We are working to resolve this as quickly as possible and will share another update shortly.

As of 9:45 PM US/Eastern on July 8, 2026, we paused processing new webhooks for product catalogs while we continue working on a fix. Catalog data, including in Templates and Customer Hub, will remain out of date until syncing resumes. Our engineering team is actively working to restore realtime catalog updates. We'll provide updates as soon as more information is available.

As of 11:13 PM US/Eastern on July 8, 2026, we have resumed processing webhooks. This means all new webhooks from integrations which use webhooks to update products are now syncing in real time. Our Engineering Team is working implement a repair to catch up on any product update webhooks from during window of impact (9:45 PM and 11:13 PM US/Eastern July 8, 2026). We will confirm once the repair has been complete and the incident has been fully resolved.

Product updates from ecommerce integrations are continuing to sync normally in real time. A background repair to fully update records from the earlier impact window (9:45 PM to 11:13 PM US/Eastern on July 8, 2026) is still in progress. We will confirm once this repair is complete.

The repair to catch up on product update webhooks from the window of impact has been completed, and affected product data is up to date. This incident has been resolved.

Customers may be experiencing slower than usual performance when loading or navigating Klaviyo, and some sends may be delayed. We are actively investigating. We will share another update as soon as we have more information.

Performance issues affecting login and general navigation in Klaviyo have recovered, and those areas are now operating normally. Some customers may still be experiencing delays with sends while we work to fully restore normal processing. We have identified the cause and are working to resolve the remaining impact as quickly as possible. We will share another update shortly.

Campaign and flow sends are now delayed by less than 30 minutes and are continuing to recover. Login and navigation are operating normally. We will share another update shortly.

Sending delays have recovered, and login and navigation are operating normally. We continue to monitor closely and appreciate your patience throughout this incident.

All systems are operating normally. This incident has been resolved.

Starting at 02:30AM US/Eastern on 07/02/2026, a subset of customers are currently experiencing an increase in bounced emails to Yahoo and AOL recipients with the reason of "554 Message not allowed - [PH01] Email not accepted for policy reasons.". Our Engineering and Deliverability teams are actively investigating and working with Yahoo to resolve the issue. We do not recommend resending to those bounced recipients at this moment in time.

The block within the Yahoo infrastructure that resulted in these elevated bounces has been resolved. Customers can safely resend to bounced recipients from this time period. This incident has been resolved.

Customers are currently experiencing issues with Meta-connected features in Klaviyo, including WhatsApp messaging, Meta integrations, and Instagram connectivity. We are investigating a disruption with an upstream provider and will share another update as soon as we have more information.

Customers may continue to experience issues with Meta-connected features in Klaviyo, including WhatsApp messaging, Meta integrations, and Instagram connectivity. This is caused by a disruption at an upstream provider that affects connections to these features. We have begun to see partial recovery, and some messages are now sending successfully. We are working to resolve this quickly and will share another update as soon as more information is available.

We are seeing further recovery with WhatsApp messaging, Meta integrations, and Instagram connectivity. WhatsApp messaging should no longer encounter failures. We've replayed all failed messages during this time period. We continue to monitor and will confirm once recovery has completed.

Meta-connected features in Klaviyo, including WhatsApp messaging, Meta integrations, and Instagram connectivity, have returned to normal. Messages that failed during the disruption were reprocessed, though a small number that did not reach Klaviyo could not be recovered. This incident has been resolved.

Customers may be experiencing an error when selecting a template while creating or editing a campaign. Our team is actively investigating and will share another update as soon as we have more information.

We have identified the root cause and are working on a fix. We will share another update shortly.

A fix has been deployed and system performance is improving. Customers should start to be able to successfully select a template. We continue to monitor closely and appreciate your patience throughout this incident.

Customers should no longer see any errors when selecting a template while creating or editing a campaign. This incident has been resolved.

Some customers may be experiencing delays with campaign sending, where sends are currently stuck in processing. We are investigating the issue and will provide an update as soon as we have more information.

We have identified the root cause and are working on a fix. We will share another update shortly.

We are continuing to work through the fix for this issue. We are working to resolve this as quickly as possible and will share another update shortly.

We have deployed a fix and campaign sending is recovering. We are processing the backlog of delayed campaigns and expect to deliver them shortly. We continue to monitor closely and appreciate your patience throughout this incident.

Campaign sending has been restored and the backlog of delayed campaigns has completed sending. This incident has been resolved.

All WhatsApp functionality is currently unavailable for customers due to an upstream provider outage (including sending, integration setup and template editing). The Engineering team is actively investigating and will share more information as soon as it becomes available.

The issue affecting WhatsApp features within Klaviyo has been resolved as of 6:45 PM US/Eastern on June 6, 2026. Our Engineering team has monitored performance and see that WhatsApp services have been restored including message sending, integration setup and template editing. This incident has been resolved.