Resend Outage History

Resend experienced increased latency in email event updates for 2.9 hours. The service identified the cause of queued events and worked through the backlog to resolve the issue. Email event processing was delayed but the system continued operating with reduced performance.

Resend experienced increased latency affecting broadcast email sending and domain verification processes for 2.8 hours. The issue was traced to a third-party provider, who implemented improvements to resolve the performance problems. Both broadcast email throughput and domain verification times returned to normal after the provider's fixes were deployed.

Resend experienced a major service incident where users encountered 404 errors when attempting to send emails through both the SMTP service and API. The issue affected email sending functionality for 1.4 hours before engineers identified the root cause and applied fixes to restore service. The incident was resolved after monitoring confirmed the fixes were successful across all affected systems.

Resend experienced increased latency in email sending that affected customers using both SMTP service and API, causing delays in email delivery. The issue was identified as affecting a subset of customers and was actively investigated by the team. The problem was resolved after 59 minutes, with all emails returning to normal delivery speeds.

Resend experienced increased latency in email event updates for 11 minutes on March 26, 2026. The service classified this as a minor incident affecting the timeliness of email event processing. The issue was under investigation during the outage period.

Resend experienced errors preventing contacts from successfully unsubscribing from audiences and segments. The unsubscribe functionality was affected, blocking users from opting out of email communications. The incident lasted 1.2 hours and was resolved.

Resend experienced delayed Email Events following scheduled maintenance, lasting 1.4 hours. The service confirmed that while events were processed with delays, no data was lost during the incident. The issue was identified and resolved without permanent impact to email functionality.

Resend experienced deliverability issues affecting emails sent to Microsoft-owned domains (Outlook.com, Hotmail.com, etc.), causing delivery delays particularly in the eu-west-1 region. The incident lasted 22.7 hours while Resend worked with Microsoft to resolve the underlying delivery problems. Email delivery to Microsoft domains returned to normal timing after the resolution.

Resend experienced increased latency in email event updates for 19 minutes on March 5th, 2026. The service classified this as a minor incident affecting the timeliness of email event processing. The issue was under investigation during the outage period.

Resend experienced increased latency in their email sending service, causing delays for users sending emails through both their SMTP service and API. The incident was resolved after 4 minutes of investigation.