MailChimp had 26 outages in the last 2 years totaling 4027h 49m of downtime — averaging 1.1 incidents per month.
There were 26 MailChimp outages since October 8, 2025 totaling 4027h 49m of downtime. Each is summarised below — incident details, duration, and resolution information.
The cause of the delayed deliveries has been mitigated. Thanks for your patience while we resolved this matter and please contact Support if you have any additional questions.
Engineers have fixed the issue that was causing delays with Audience updates and the All Contacts table. We thank you for your patience.
Engineers have addressed the issue that was causing sending delays with select Mandril/Transactional accounts. Sends are going out. We thank you for your patience.
At approximately 10am EST, we began receiving reports of links in Campaigns resulting in "500" errors. A fix was deployed and has since been resolved.
We have identified and resolved an issue due to campaign links not being tracked correctly. Tracking has been fully restored; however, click tracking during the affected window (starting around 11:00 AM EST on August 3rd to 12:00 PM EST on August 4th) cannot be backfilled. This will impact areas such as campaign reporting sent during this window. We sincerely apologize for the inconvenience.
Our Engineering team has resolved the reporting issues with All Campaigns Page showing 0% Opens and Clicks. Thank you for your patience.
We are currently aware of and investigating an issue with contacts not entering Flow Automations after signup for a subset of Mailchimp accounts. Our Engineering team is working on a resolution and we will provide further updates as they become available.
Engineers have resolved the issue with the subset of Mailchimp accounts that experienced contacts not entering Flow Automations after signup. We thank you for your patience.
Engineers have resolved the issue with Mailchimp Transactional (formerly Mandrill) connectivity issues and sending delays. We thank you for your patience.
All services that were impacted by the Google outage are fully operational.
Engineers have resolved an issue preventing changes in contact counts from updating on the Audience Analytics page and Homepage. Contacts added or removed during May 7–13 were recorded correctly. However, reporting for contact count changes during this period is unavailable, so charts and trend indicators may not reflect increases or decreases accurately.
Earlier today, the Mailchimp Transactional API was intermittently returning SSL errors between 10:45 AM – 12:10 PM PT, during which a subset of customers saw intermittent failures for their API requests.
We have identified and resolved the issue affecting campaign delivery and service is now operating normally. We appreciate your patience.
Our Engineering team has resolved the issue with Segmentation and sending of new Campaigns. Thank you for your patience.
Issues affecting stuck Exports have been resolved. Thank you for your patience in this matter.
Our Engineering team has resolved the issue with Segmentation and sending of new Campaigns. Thank you for your patience.
Our team has resolved the issue with eepUrls and all affected URLs are now fixed. Thank you for your patience.
We have identified and resolved the issue affecting campaign delivery. Service is now operating normally. We appreciate your patience.
Our Engineering team has resolved the issues with Campaigns stuck in a Preparing/Sending status. Thank you for your patience.
Application maintenance is complete and performance is fully restored. Thank you for your patience while our team worked through updates.
Our engineering team has resolved the issues impacting Segments and Audience data. We appreciate your patience and apologize for any disruption this may have caused.
Our engineers have resolved the issue affecting campaign loading. We appreciate your patience. If you continue to experience issues, please try clearing your browser’s cache and cookies.
The issue affecting template visibility has been fully resolved. All templates should now appear as expected. We appreciate your patience while our team worked on this fix.
Our Engineering team has resolved the reporting issues. Campaign data, including opens and clicks, is now up to date. Thank you for your patience.
All services that were impacted by the AWS outage are fully operational.
We’ve resolved issues impacting both test emails and campaign sending. Thank you for your patience while our Engineering team worked to restore functionality.