Aug <var data-var='date'>19</var>, <var data-var='time'>14:38</var> EDT Resolved - 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. Aug <var data-var='date'>19</var>, <var data-var='time'>14:13</var> EDT Monitoring - 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. Aug <var data-var='date'>19</var>, <var data-var='time'>13:15</var> EDT Identified - 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.

Delays in real-time segmentation

Aug <var data-var='date'>12</var>, <var data-var='time'>14:14</var> EDT 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. Aug <var data-var='date'>12</var>, <var data-var='time'>14:04</var> EDT Monitoring - 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 errors

Aug <var data-var='date'> 6</var>, <var data-var='time'>21:47</var> EDT Completed - The scheduled maintenance has been completed Aug <var data-var='date'> 6</var>, <var data-var='time'>21:02</var> EDT Update - Scheduled maintenance is currently in progress. We will provide updates as necessary. Aug <var data-var='date'> 6</var>, <var data-var='time'>21:00</var> EDT In progress - Scheduled maintenance is currently in progress. We will provide updates as necessary. Aug <var data-var='date'> 5</var>, <var data-var='time'>11:53</var> EDT Scheduled - Beginning at 9:00 PM US/Eastern on Thursday, August 6, 2026, Klaviyo will perform scheduled maintenance on the infrastructure that supports login, including single sign-on (SSO) and multi-factor authentication (MFA). We expect the maintenance period to last approximately 1 hour. We do not anticipate any disruption during this window. As a precaution, there is a small possibility that logging in to Klaviyo, or authenticating through SSO or MFA, could be briefly affected. Please note that no data will be lost during this maintenance and these services will continue to work as normal once maintenance has completed.

Login/MFA Maintenance

Aug <var data-var='date'> 5</var>, <var data-var='time'>13:54</var> EDT Resolved - 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. Aug <var data-var='date'> 5</var>, <var data-var='time'>13:36</var> EDT Monitoring - 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. Aug <var data-var='date'> 5</var>, <var data-var='time'>13:26</var> EDT Identified - 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. Aug <var data-var='date'> 5</var>, <var data-var='time'>12:47</var> EDT Investigating - 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.

Delays affecting campaign scheduling, preview emails, and double opt-in confirmations

Jul <var data-var='date'>23</var>, <var data-var='time'>12:01</var> EDT Resolved - 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. Jul <var data-var='date'>23</var>, <var data-var='time'>11:16</var> EDT Monitoring - 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. Jul <var data-var='date'>23</var>, <var data-var='time'>10:35</var> EDT Identified - 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.

Sync Tasks Failing

Jul <var data-var='date'>21</var>, <var data-var='time'>17:09</var> EDT Resolved - SMS subscriptions, SMS sending, and the creation and scheduling of SMS and WhatsApp campaigns are operating as expected. This incident has been resolved. Jul <var data-var='date'>21</var>, <var data-var='time'>16:57</var> EDT Monitoring - 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. Jul <var data-var='date'>21</var>, <var data-var='time'>16:47</var> EDT Identified - We have identified the cause of the issue and a fix has been implemented. We are starting to see improvements in system performance. Jul <var data-var='date'>21</var>, <var data-var='time'>16:36</var> EDT Investigating - 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.

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

Jul <var data-var='date'>10</var>, <var data-var='time'>17:01</var> EDT Resolved - 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. Jul <var data-var='date'> 9</var>, <var data-var='time'>12:13</var> EDT Update - 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. Jul <var data-var='date'> 9</var>, <var data-var='time'>00:34</var> EDT Monitoring - 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. Jul <var data-var='date'> 8</var>, <var data-var='time'>23:14</var> EDT Identified - 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. Jul <var data-var='date'> 8</var>, <var data-var='time'>21:52</var> EDT Investigating - 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.

Catalog Webhook Processing Delays

Jul <var data-var='date'> 9</var>, <var data-var='time'>19:00</var> EDT Completed - The scheduled maintenance has been completed. Jul <var data-var='date'> 9</var>, <var data-var='time'>18:00</var> EDT In progress - Scheduled maintenance is currently in progress. We will provide updates as necessary. Jul <var data-var='date'> 8</var>, <var data-var='time'>12:05</var> EDT Scheduled - Beginning at 6:00 PM US/Eastern on Thursday, July 9, 2026, Klaviyo's Engineering team will perform maintenance on our infrastructure for consent. We expect the maintenance period to last approximately 1 hour. During this time, in-app and API operations related to SMS and Whatsapp Consent may be temporarily unavailable. This includes subscribes and unsubscribes. Please note that no data will be lost during this maintenance and these features should run as expected once maintenance has completed.

Data Infrastructure Maintenance

Jul <var data-var='date'> 7</var>, <var data-var='time'>12:56</var> EDT Resolved - All systems are operating normally. This incident has been resolved. Jul <var data-var='date'> 7</var>, <var data-var='time'>12:47</var> EDT Monitoring - Sending delays have recovered, and login and navigation are operating normally. We continue to monitor closely and appreciate your patience throughout this incident. Jul <var data-var='date'> 7</var>, <var data-var='time'>12:32</var> EDT Update - 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. Jul <var data-var='date'> 7</var>, <var data-var='time'>11:56</var> EDT Identified - 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. Jul <var data-var='date'> 7</var>, <var data-var='time'>11:33</var> EDT Investigating - 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.

Klaviyo Loading Errors and Sending Delays

Jul <var data-var='date'> 6</var>, <var data-var='time'>19:02</var> EDT Completed - The scheduled maintenance has been completed. Jul <var data-var='date'> 6</var>, <var data-var='time'>18:02</var> EDT In progress - Scheduled maintenance is currently in progress. We will provide updates as necessary. Jul <var data-var='date'> 6</var>, <var data-var='time'>18:01</var> EDT Scheduled - Beginning at 6:00 PM (US Eastern Time) on Monday, July 6, 2026, Klaviyo's Engineering team will perform maintenance on our infrastructure for consent. We expect the maintenance period to last approximately 1 hour. During this time, in-app and API operations related to SMS and Whatsapp Consent may be temporarily unavailable. This includes subscribes and unsubscribes. Please note that no data will be lost during this maintenance and these features should run as expected once maintenance has completed.

Jul <var data-var='date'> 2</var>, <var data-var='time'>10:17</var> EDT Resolved - 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. Jul <var data-var='date'> 2</var>, <var data-var='time'>08:17</var> EDT Investigating - 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.

Yahoo PH01 Block — Email Bounces to Yahoo/AOL Recipients

Jun <var data-var='date'>12</var>, <var data-var='time'>13:30</var> EDT Resolved - 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. Jun <var data-var='date'>12</var>, <var data-var='time'>13:19</var> EDT Monitoring - 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. Jun <var data-var='date'>12</var>, <var data-var='time'>11:48</var> EDT Identified - 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. Jun <var data-var='date'>12</var>, <var data-var='time'>10:49</var> EDT Investigating - 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.

Meta Services Disruption

Jun <var data-var='date'>10</var>, <var data-var='time'>15:46</var> EDT Resolved - Customers should no longer see any errors when selecting a template while creating or editing a campaign. This incident has been resolved. Jun <var data-var='date'>10</var>, <var data-var='time'>15:23</var> EDT Monitoring - 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. Jun <var data-var='date'>10</var>, <var data-var='time'>15:02</var> EDT Identified - We have identified the root cause and are working on a fix. We will share another update shortly. Jun <var data-var='date'>10</var>, <var data-var='time'>14:47</var> EDT Investigating - 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.

Errors when attempting to select templates for campaigns

Jun <var data-var='date'> 8</var>, <var data-var='time'>20:49</var> EDT Resolved - Campaign sending has been restored and the backlog of delayed campaigns has completed sending. This incident has been resolved. Jun <var data-var='date'> 8</var>, <var data-var='time'>19:54</var> EDT Monitoring - 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. Jun <var data-var='date'> 8</var>, <var data-var='time'>19:20</var> EDT Update - 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. Jun <var data-var='date'> 8</var>, <var data-var='time'>17:19</var> EDT Identified - We have identified the root cause and are working on a fix. We will share another update shortly. Jun <var data-var='date'> 8</var>, <var data-var='time'>17:10</var> EDT Investigating - 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.

Campaign sending delays

Jun <var data-var='date'> 6</var>, <var data-var='time'>19:05</var> EDT Resolved - 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. Jun <var data-var='date'> 6</var>, <var data-var='time'>13:18</var> EDT Investigating - 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.

WhatsApp Disruption

Jun <var data-var='date'> 3</var>, <var data-var='time'>13:16</var> EDT Resolved - The issue affecting Shopify integrations has been resolved, and Shopify data syncing has returned to normal. Automated retry processes will continue to work through the backlog of affected requests. Some customers may see their integration in a failed state, but the retry processes will automatically fix this. Customers who saw errors while setting up a new Shopify integration can retry. This incident has been resolved. Jun <var data-var='date'> 3</var>, <var data-var='time'>11:06</var> EDT Monitoring - We're seeing further recovery for Shopify integrations, and Shopify data syncing is returning to normal. Automated retry processes are working through the backlog of affected requests. No action is required for customers with existing integrations. Customers who saw errors while setting up a new Shopify integration can retry that setup. We continue to monitor closely and appreciate your patience throughout this incident. Jun <var data-var='date'> 3</var>, <var data-var='time'>10:46</var> EDT Identified - The issue has been identified and we are seeing early signs of recovery. We are continuing to monitor the situation closely and will share another update shortly. Jun <var data-var='date'> 3</var>, <var data-var='time'>10:23</var> EDT Investigating - Klaviyo is aware of an issue affecting the Shopify integration. Some customers attempting to set up a new Shopify integration, or performing actions that depend on the Shopify API, may be encountering errors. Customers with existing integrations may experience delays in Shopify data syncing. The issue is caused by a partial outage affecting an upstream service, and our team is actively monitoring the situation while automated retry processes work to recover affected requests. You can follow the external incident here: https://www.shopifystatus.com/incidents/gbqcx5fk01gz We will share more as soon as the situation is understood.

Shopify API Outage

May <var data-var='date'>19</var>, <var data-var='time'>20:30</var> EDT Resolved - 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. May <var data-var='date'>19</var>, <var data-var='time'>18:21</var> EDT Identified - 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. May <var data-var='date'>19</var>, <var data-var='time'>16:36</var> EDT Investigating - 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.

SMS Event Processing Delays

May <var data-var='date'>19</var>, <var data-var='time'>13:38</var> EDT Resolved - The intermittent errors, slow page loads, and delays for email and SMS sends have been resolved. A small number of push notifications from impacted flows are being replayed and will deliver shortly. This incident has been resolved. May <var data-var='date'>19</var>, <var data-var='time'>13:17</var> EDT Monitoring - A fix has been deployed and system performance is improving. Intermittent errors, slow page loads, and delays for email and SMS sends are recovering. We continue to monitor closely. May <var data-var='date'>19</var>, <var data-var='time'>12:46</var> EDT Identified - We have identified the cause of the intermittent errors and slow page loads some customers are experiencing in the Klaviyo app. Some customers may also be experiencing delays of up to 20 minutes for email and SMS sends, as well as delays in flows that send push notifications. Our engineering team is deploying a fix. May <var data-var='date'>19</var>, <var data-var='time'>12:11</var> EDT Investigating - Customers may be experiencing intermittent errors and slow page loads in the Klaviyo app. Our engineering team is actively investigating. We'll provide updates as soon as more information is available.

Page loading errors

May <var data-var='date'> 8</var>, <var data-var='time'>20:31</var> EDT Resolved - Analytics processing for campaigns and flows is fully caught up and operating normally. We appreciate your patience throughout this incident. This incident has been resolved. May <var data-var='date'> 8</var>, <var data-var='time'>19:13</var> EDT Monitoring - Analytics processing for campaigns and flows is recovering and the delay is decreasing. Sending, scheduling, and other core functions remain fully operational. We're monitoring closely and will confirm once analytics return to normal operation. May <var data-var='date'> 8</var>, <var data-var='time'>16:19</var> EDT Update - Sending, scheduling, and other core functions are operating normally. Analytics for campaigns and flows are currently delayed by approximately 2 hours. These issues are tied to instability with an upstream infrastructure provider (AWS) and we are continuing to work through them. We'll provide updates as soon as we have more to share. May <var data-var='date'> 8</var>, <var data-var='time'>14:37</var> EDT Update - System performance is improving, and users can now access campaigns pages to complete scheduling. We determined these errors resulted from a combination of instability with an upstream infrastructure provider (AWS) and a significant increase in retry traffic. We continue to monitor closely and appreciate your patience throughout this incident. May <var data-var='date'> 8</var>, <var data-var='time'>13:10</var> EDT Identified - We have identified the root cause of the errors and our engineering team is actively working toward a resolution. We'll provide updates as soon as more information is available. May <var data-var='date'> 8</var>, <var data-var='time'>11:02</var> EDT Investigating - We are currently investigating reports of errors loading campaign and flow pages within Klaviyo. Campaign and flow sending is not impacted. Our engineering team is actively working to identify and resolve the issue. We'll provide updates as soon as more information is available.

Campaign and flow page loading errors

May <var data-var='date'> 8</var>, <var data-var='time'>15:05</var> EDT Resolved - Segmentation continues to process in real-time and is fully recovered. We determined the delays resulted from instability with an upstream infrastructure provider (AWS). This incident is now resolved. May <var data-var='date'> 8</var>, <var data-var='time'>12:59</var> EDT Monitoring - Segmentation has been restored to real-time processing, and campaign and forms analytics have now recovered. This was a reporting UI display issue only, no data was lost. Our engineering team continues to monitor closely until our upstream service provider has confirmed full recovery. May <var data-var='date'> 8</var>, <var data-var='time'>03:08</var> EDT Update - Segmentation has been restored to realtime processing. Our engineering team continues to restore the remaining affected analytics. We will continue to provide updates as real-time analytics functionality resumes. May <var data-var='date'> 7</var>, <var data-var='time'>23:46</var> EDT Update - A subset of customers are currently experiencing segmentation processing delays of approximately 1.5 hours and may find that analytics data is not fully up to date. Access to reporting pages has been restored and our engineering team is actively working to bring segmentation and analytics back to real time. We'll provide updates as soon as more information is available. May <var data-var='date'> 7</var>, <var data-var='time'>22:22</var> EDT Identified - Our engineering team continues to investigate areas affected by an upstream service provider. Customers may experience processing delays for segmentation and analytics, and loading issues with reporting pages. For campaigns, sends may not reach the most up-to-date audience due to segmentation delays. Segment-triggered flows may also fail to trigger correctly as profiles may not be added to or removed from segments as expected. We'll provide updates as soon as more information is available. May <var data-var='date'> 7</var>, <var data-var='time'>21:32</var> EDT Investigating - We are currently investigating an issue affecting analytics and reporting, flows, campaigns, and segmentation. This issue appears to be related to a disruption with an upstream service provider. Customers may experience errors or be unable to load flows and campaigns pages, see delays in real-time segmentation updates, and find analytics data temporarily unavailable. Our team is actively working to resolve this. We'll provide updates as soon as more information is available.

Processing delays

May <var data-var='date'> 7</var>, <var data-var='time'>19:02</var> EDT Resolved - All Klaviyo services have been fully restored and final recovery work is complete. We appreciate your patience throughout this incident. This incident has been resolved. May <var data-var='date'> 7</var>, <var data-var='time'>11:48</var> EDT Update - Klaviyo services remain restored and operating as expected. Most recovery and repair work is now complete. Remaining work is focused on restoring webhook connections for a subset of WooCommerce and Eventbrite integrations and a subset of campaign analytics repairs, neither of which is affecting customer use of the platform. Our team is continuing to monitor closely. May <var data-var='date'> 6</var>, <var data-var='time'>17:30</var> EDT Update - Klaviyo services remain restored and operating as expected. Final background recovery and repair work is ongoing, but is not affecting customer use of the platform. Our team is continuing to monitor closely. May <var data-var='date'> 6</var>, <var data-var='time'>11:59</var> EDT Update - Klaviyo services have been restored. Some background data reconciliation and recovery work is still in progress. This is not affecting overall system availability or customer use of the platform. Our team is continuing to monitor closely as we complete final repair efforts. May <var data-var='date'> 6</var>, <var data-var='time'>01:59</var> EDT Update - Access to klaviyo.com and core platform services has been restored. The majority of platform areas have returned to normal operation, with many affected services recovering automatically as infrastructure came back online. Our team is continuing to monitor platform stability and is actively working through remaining data repairs, including unsubscribe processing and analytics recovery. We will share further updates as this work progresses. May <var data-var='date'> 5</var>, <var data-var='time'>22:53</var> EDT Monitoring - Our engineering team has restored the impacted services and confirmed that systems have resumed functioning as intended. All Campaign/Flow messages impacted which are able to be replayed are currently sending. We're currently monitoring performance and will continue to update as incident is resolved. May <var data-var='date'> 5</var>, <var data-var='time'>21:38</var> EDT Update - We are seeing recovery across APIs, event ingestion, and subscriptions. Our team continues to work toward restoring full functionality. May <var data-var='date'> 5</var>, <var data-var='time'>20:57</var> EDT Update - Recovery is continuing to progress, and additional services are coming back online. Our team remains actively engaged, and we'll provide another update shortly. May <var data-var='date'> 5</var>, <var data-var='time'>20:25</var> EDT Identified - Access to klaviyo.com has been restored, and dependent services are progressively coming back online. Our team continues to work toward full recovery, which we expect within the next hour. We'll provide another update in 30 minutes. May <var data-var='date'> 5</var>, <var data-var='time'>19:40</var> EDT Update - We are continuing to investigate the issue affecting access to klaviyo.com and all associated services. Our engineering team is actively working to restore affected services. We will provide updates as soon as more information is available. May <var data-var='date'> 5</var>, <var data-var='time'>18:33</var> EDT Update - Our engineering team is continuing to investigate the disruption affecting klaviyo.com, our APIs, and message sending. We will provide updates as more information is available. May <var data-var='date'> 5</var>, <var data-var='time'>17:24</var> EDT Investigating - Klaviyo is currently experiencing a service disruption affecting access to klaviyo.com, our APIs, and message sending. Customers may be unable to log in, send campaigns or flows, or have their events processed during this time. Our engineering team is actively investigating the root cause. We'll provide updates as soon as more information is available.

Klaviyo Service Disruption

Apr <var data-var='date'>26</var>, <var data-var='time'>04:11</var> EDT Resolved - We confirmed that all API activity has been stable since the fix was released. Any requests that returned 503 errors during the outage window will need to be retried. This incident has been resolved. Apr <var data-var='date'>26</var>, <var data-var='time'>03:43</var> EDT Monitoring - We successfully implemented a fix as of 3:20 AM US/Eastern that restored all API activity. We are continuing to monitor the results. Apr <var data-var='date'>26</var>, <var data-var='time'>03:24</var> EDT Identified - Starting at approximately 2:27 AM US/Eastern on 04/25/2026, we began experiencing intermittent elevated errors across our APIs. Some customers may experience 503 errors when trying to log into Klaviyo, load certain pages or make API requests. Our Engineering Team has identified the root cause and has implemented mitigations. We'll provide updates as soon as more information is available.

API 503 Errors

Mar <var data-var='date'>27</var>, <var data-var='time'>01:15</var> EDT Resolved - Real-time segmentation is processing in real-time, and this incident has been resolved. Mar <var data-var='date'>27</var>, <var data-var='time'>00:46</var> EDT Monitoring - Starting around 8:15 PM US Eastern 26th March, we began seeing delays in real-time segment processing for a subset of customers. Segments may be out of date by up to 2.5 hours. Engineering have identified a solution and are working to implement the fix shortly. We will continue to provide updates as real-time segmentation functionality is restored.

Real-time segmentation delays

Jan <var data-var='date'>12</var>, <var data-var='time'>07:23</var> EST Resolved - This incident has been resolved. Jan <var data-var='date'>12</var>, <var data-var='time'>07:05</var> EST Monitoring - A fix has been implemented and we are monitoring results. Campaign sending and scheduling is back to normal, and all delayed campaigns have been replayed. Jan <var data-var='date'>12</var>, <var data-var='time'>06:51</var> EST Identified - As of 6:45am US Eastern, the issue has been identified and a fix implemented. Any new scheduled or sent campaigns should process, with slight delays. We are actively replaying any campaigns that were delayed. Jan <var data-var='date'>12</var>, <var data-var='time'>06:12</var> EST Investigating - Beginning around 5am US Eastern time, we began observing delays in campaign scheduling and sending. New campaigns, and scheduled RAST (calculate Recipient at Send Times) campaigns, are unable to send. However non-RAST campaigns that were scheduled prior to 5am US Eastern Time are processing as usual. We do not expect data loss. We are actively working to resolve the incident and will provide updates as soon as possible.

Issues with Campaign Sending and Scheduling

Dec <var data-var='date'>22</var>, <var data-var='time'>19:07</var> EST Resolved - This incident has been resolved. Dec <var data-var='date'>22</var>, <var data-var='time'>18:58</var> EST Monitoring - We have confirmed the app is now widely available and are moving the incident to monitoring. 10% of accounts experienced messaging delays during this window. We are working to replay any impacted messages, including unsubscribes, inbound SMS, and flows. Any campaigns that failed during this time will need to be manually resent. We will continue to monitor system performance. Dec <var data-var='date'>22</var>, <var data-var='time'>18:37</var> EST Update - We identified broader service disruption across the Klaviyo app between 5:55 pm and approximately 6:10 pm ET. While initial reports were limited to account switching, we have since confirmed additional impact to app availability and functionality. The underlying issue has been addressed, and the app is now available. Some customers may continue to experience intermittent issues as systems fully recover. We are actively monitoring. Dec <var data-var='date'>22</var>, <var data-var='time'>17:37</var> EST Investigating - We are investigating reports of users unable to switch accounts once logged into Klaviyo

Is Klaviyo down?

Klaviyo status is UP

Lastest published events

Delays in real-time segmentation

Campaign scheduling errors

Login/MFA Maintenance

Klaviyo Services, Components and Regions

Recent Klaviyo events

Delays in real-time segmentation

Campaign scheduling errors

Login/MFA Maintenance

Delays affecting campaign scheduling, preview emails, and double opt-in confirmations

Sync Tasks Failing

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