Lettermint incident
[Blocklist] Transactional IP listed in Spamhaus
Lettermint experienced a minor incident on June 23, 2026, lasting —. The incident has been resolved; the full update timeline is below.
Update timeline
- identified Jun 23, 2026, 06:01 AM UTC
Status: Identified We’ve identified that three of our outbound transactional IP addresses have been blocklisted, affecting email delivery for some customers. The team is currently investigating the cause and working on delisting the IP. In the meantime, the IP address has been suspended and will not be used until the issue is resolved. This does not affect other IPs in the pool nor broadcast routes. If you have seen a hard bounce because of this, you can safely reactivate the recipient from your suppression management.
- identified Jun 23, 2026, 08:41 AM UTC
Status: Identified We are still actively working on this issue. An update from Spamhaus was received ~20 minutes ago and delisting is being propagated worldwide. We will keep monitoring the situation. Our sincere apologies for the inconvenience.
- identified Jun 23, 2026, 10:47 AM UTC
Status: Identified We are still actively working on this issue and are awaiting an update from Spamhaus. We will keep monitoring the situation. Our sincere apologies for the inconvenience.
- identified Jun 23, 2026, 01:38 PM UTC
Status: Identified We are still actively working on this issue and are awaiting an update from Spamhaus. We will keep monitoring the situation. Our sincere apologies for the inconvenience.
- monitoring Jun 23, 2026, 03:14 PM UTC
Status: Monitoring We’ve been in contact with Spamhaus and the delisting process has now been successfully applied. The delisting has been put into effect, but mail providers that rely on Spamhaus may take some time to refresh and propagate these changes within their own systems and internal caches. We are currently monitoring the situation closely while these updates continue to propagate. Once we determine that delivery has stabilized and it is safe to proceed, we will begin retrying affected emails that were not yet successfully delivered and provide further updates as needed.
- resolved Jun 23, 2026, 04:24 PM UTC
Status: Resolved We are not seeing anymore bounces related to the Spamhaus listing and are working on resending all impacted messages. Due to the length and impact of this incident we will share a post-mortem on this incident. Apologies for the inconvenience this has caused.