Substack experienced a minor incident on October 4, 2025 affecting Email delivery and Push Notifications, lasting 4h 22m. The incident has been resolved; the full update timeline is below.
Affected components
Email deliveryPush Notifications
Update timeline
- investigating Oct 04, 2025, 04:06 PM UTC
We are experiencing delays in sending out email and push notifications for published posts.
- identified Oct 04, 2025, 04:25 PM UTC
The issue has been identified and a fix is being implemented.
- monitoring Oct 04, 2025, 07:22 PM UTC
A fix has been implemented and we are monitoring the results.
- resolved Oct 04, 2025, 08:29 PM UTC
This incident has been resolved.