Lettermint Outage History

Lettermint had 24 outages in the last 2 years totaling 111h 8m of downtime — averaging 1 incident per month.

There were 24 Lettermint outages since September 26, 2025 totaling 111h 8m of downtime. Each is summarised below — incident details, duration, and resolution information.

Source: https://status.lettermint.co

Minor June 17, 2026

Email submissions not being processed

Detected by Pingoru: Jun 17, 2026, 08:18 PM UTC
Resolved: Jun 17, 2026, 08:18 PM UTC
Duration: —

Affected: IncomingSMTP Relay

Timeline · 5 updates

investigating Jun 17, 2026, 05:00 PM UTC

Status: Investigating We are currently investigating reports of email submitted via the SMTP relay not being processed. Affected components SMTP Relay (Full outage) Incoming (Full outage)
identified Jun 17, 2026, 05:52 PM UTC

Status: Identified We have identified the issue and our team is working on a fix. We'll keep you posted. Apologies for the inconvenience. Affected components Incoming (Full outage) SMTP Relay (Full outage)
monitoring Jun 17, 2026, 06:06 PM UTC

Status: Monitoring A fix is being deployed and we'll be monitoring the situation. Affected components Incoming (Full outage) SMTP Relay (Full outage)
monitoring Jun 17, 2026, 06:09 PM UTC

Status: Monitoring We are seeing improvements and services are back to normal. In the meantime, we will keep monitoring the situation closely and apologies for the inconvenience this has caused. A public post-mortem will also be shared. Affected components Incoming (Operational) SMTP Relay (Operational)
resolved Jun 17, 2026, 08:18 PM UTC

Status: Resolved We have continued monitoring and have not observed any further recurrence of this issue. The incident is now resolved. We have completed a post-mortem and will publish it shortly with more detail on the impact, root cause, and follow-up actions. Affected components SMTP Relay (Operational) Incoming (Operational)

Read the full incident report →

Minor May 29, 2026

Delay in sending emails

Detected by Pingoru: May 29, 2026, 01:20 PM UTC
Resolved: May 29, 2026, 01:20 PM UTC
Duration: —

Timeline · 4 updates

investigating May 29, 2026, 10:59 AM UTC

Status: Investigating We are currently investigating a sudden increase in queue times for emails. Emails are delayed for ~2 minutes on average. We will keep you posted. Affected components Outgoing (Transactional) (Degraded performance) Outgoing (Broadcast) (Degraded performance)
identified May 29, 2026, 11:09 AM UTC

Status: Identified We have identified the issue causing a delay in processing of emails and are working on a fix. Currently emails are in queue for an average of ~22 seconds, higher than the usual average of a couple milliseconds. We will keep you posted once a fix has been implemented. Affected components Outgoing (Transactional) (Degraded performance) Outgoing (Broadcast) (Degraded performance)
monitoring May 29, 2026, 12:00 PM UTC

Status: Monitoring A fix has been implemented and we're monitoring the situation. Queues are being processed quickly again and the time-to-inbox dropped to sub-10 seconds as expected. Apologies for the inconvenience this caused. Affected components Outgoing (Transactional) (Operational) Outgoing (Broadcast) (Operational)
resolved May 29, 2026, 01:20 PM UTC

Status: Resolved We have not seen any regressions related to emails being queued for longer than expected. Therefore we're marking this incident as resolved. If you still notice any issues, do reach out to support. Affected components Outgoing (Transactional) (Operational) Outgoing (Broadcast) (Operational)

Read the full incident report →

Minor April 7, 2026

Time-outs with larger emails

Detected by Pingoru: Apr 07, 2026, 08:31 PM UTC
Resolved: Apr 07, 2026, 08:31 PM UTC
Duration: —

Affected: SMTP Relay

Timeline · 3 updates

investigating Apr 07, 2026, 06:43 PM UTC

Status: Investigating We are noticing degraded performance with sending larger attachment to our SMTP relay and are currently investigating the issue. Affected components SMTP Relay (Degraded performance)
monitoring Apr 07, 2026, 07:52 PM UTC

Status: Monitoring Fix has been deployed for the intermittent connection errors affecting SMTP submissions with larger attachments. We are now observing traffic to confirm the issue is fully resolved. No action is required from customers. Affected components SMTP Relay (Operational)
resolved Apr 07, 2026, 08:31 PM UTC

Status: Resolved We are no longer seeing any connection issues. A post-mortem will be shared as soon as possible. Our findings have been shared with the developer of the package and will cooperate to fix the issue for the ecosystem. Affected components SMTP Relay (Operational)

Read the full incident report →

Minor March 27, 2026

Email sending API degraded

Detected by Pingoru: Mar 27, 2026, 06:53 PM UTC
Resolved: Mar 27, 2026, 06:53 PM UTC
Duration: —

Affected: Sending API

Timeline · 3 updates

identified Mar 27, 2026, 06:24 PM UTC

Status: Identified We have identified the issue with our email sending API and are working on a fix. SMTP is not affected. We will provide updates as soon as we have more information. Affected components Sending API (Partial outage)
monitoring Mar 27, 2026, 06:32 PM UTC

Status: Monitoring We have deployed a fix for the issues with our email sending API. We are no longer seeing errors and will continue to monitor. Affected components Sending API (Operational)
resolved Mar 27, 2026, 06:53 PM UTC

Status: Resolved This incident is resolved. Our email sending API is fully operational and we are no longer seeing any errors or alerts. Affected components Sending API (Operational)

Read the full incident report →

Minor March 25, 2026

Intermittent delay in delivery

Detected by Pingoru: Mar 25, 2026, 08:56 AM UTC
Resolved: Mar 25, 2026, 08:56 AM UTC
Duration: —

Timeline · 3 updates

investigating Mar 25, 2026, 07:36 AM UTC

Status: Investigating We are observing an increased amount of softbounces due to issues related to networking and are currently investigating. Only a small percentage of traffic is impacted and will be retried in minutes. Affected components Outgoing (Transactional) (Degraded performance) Outgoing (Broadcast) (Degraded performance)
monitoring Mar 25, 2026, 08:28 AM UTC

Status: Monitoring The root cause has been identified and a fix has been implemented. We will keep monitoring the results, all emails are now being forced to retry immediately. Affected components Outgoing (Transactional) (Operational) Outgoing (Broadcast) (Operational)
resolved Mar 25, 2026, 08:56 AM UTC

Status: Resolved We are no longer seeing any issues and are marking this incident as resolved. We apologise for the inconvenience this may have caused. Affected components Outgoing (Transactional) (Operational) Outgoing (Broadcast) (Operational)

Read the full incident report →

Minor March 5, 2026

Intermittent increased latency and error rate

Detected by Pingoru: Mar 05, 2026, 11:11 AM UTC
Resolved: Mar 05, 2026, 11:11 AM UTC
Duration: —

Affected: Lettermint websiteIncomingTeam APILettermint UISMTP RelaySending API

Timeline · 5 updates

investigating Mar 05, 2026, 09:26 AM UTC

Status: Investigating We are investigating possible issues related to accessing Lettermint services. Updates will be shared as soon as we know more. Affected components Sending API (Partial outage) Team API (Partial outage) Incoming (Partial outage) SMTP Relay (Partial outage)
monitoring Mar 05, 2026, 09:40 AM UTC

Status: Monitoring We are monitoring the situation following an infrastructure node failure in one of our availability zones. Read database queries experienced degradation for approximately 72 seconds between 09:21–09:23 UTC impacting authentication during email submission and other endpoints. Write operations and cache services were unaffected throughout. All services have fully recovered. Affected components SMTP Relay (Operational) Sending API (Operational) Team API (Operational) Incoming (Operational)
identified Mar 05, 2026, 10:07 AM UTC

Status: Identified We have received an update to the cause of this incident, which is in fact not related to a node hardware failure as previously thought. Our cloud provider has accidentally triggered a rolling replacement of all cluster nodes in our EU-West region. This process is ongoing and may cause intermittent latency spikes or brief errors as workloads migrate and failover between nodes. Impact should be minimal. Our team is in contact with our cloud provider to receive updates on the resolution. We will provide updates as the situation develops. Affected components Lettermint UI (Degraded performance) Lettermint website (Degraded performance) Sending API (Degraded performance) Team API (Degraded performance) Incoming (Degraded performance) SMTP Relay (Degraded performance)
monitoring Mar 05, 2026, 10:22 AM UTC

Status: Monitoring Our cloud provider confirmed the roll-out was stopped. We are also no longer observing any more nodes being replaced for the last 30 minutes. All services are healthy again and we will keep monitoring the situation. Affected components Lettermint UI (Operational) Lettermint website (Operational) Sending API (Operational) Team API (Operational) Incoming (Operational) SMTP Relay (Operational)
resolved Mar 05, 2026, 11:11 AM UTC

Status: Resolved No more regressions have been noticed and all services are still healthy. Incident has been resolved. A follow-up from our cloud provider is still expected and we are taking measures to prevent issues like this in the long-term. Affected components SMTP Relay (Operational) Lettermint UI (Operational) Lettermint website (Operational) Sending API (Operational) Team API (Operational) Incoming (Operational)

Read the full incident report →

Minor February 18, 2026

[Ratelimit] Broadcast IP is rate-limited with Outlook (OLC)

Detected by Pingoru: Feb 18, 2026, 01:08 AM UTC
Resolved: Feb 18, 2026, 01:08 AM UTC
Duration: —

Timeline · 3 updates

identified Feb 17, 2026, 03:24 PM UTC

Status: Identified We've identified that two of our outbound broadcast IP addresses have been ratelimited, affecting email delivery for some customers. The team is currently investigating the cause and working on delisting the IPs. In the meantime, the IP addresses has been suspended and will not be used until the issue is resolved. This does not affect other IPs in the pool nor transactional routes. These rate limits cause soft-bounces. We will keep retrying to send the emails. Affected components Outgoing (Broadcast) (Degraded performance)
monitoring Feb 17, 2026, 04:26 PM UTC

Status: Monitoring We're no longer seeing any bounces, but we'll keep monitoring it. Affected components Outgoing (Broadcast) (Operational)
resolved Feb 18, 2026, 01:08 AM UTC

Status: Resolved We are no longer seeing any deferrals related to these IP addresses and emails are sent out accordingly. Affected components Outgoing (Broadcast) (Operational)

Read the full incident report →

Minor February 13, 2026

[Blocklist] Intermittent mailblocks to iCloud addresses

Detected by Pingoru: Feb 13, 2026, 05:27 PM UTC
Resolved: Feb 13, 2026, 05:27 PM UTC
Duration: —

Timeline · 2 updates

investigating Feb 13, 2026, 03:20 PM UTC

Status: Investigating We've been notified of intermittent delivery failures due to hard bounces to iCloud, affecting email delivery for some customers. The team is currently investigating the cause and working on resolving this issue. If you have seen a hard bounce because of this you can safely reactivate the recipient from your suppression management.
resolved Feb 13, 2026, 05:27 PM UTC

Status: Resolved We see improvements and no more bounces related to the block. After further investigation, iCloud was having issues where it was incorrectly rejecting mail with IP block responses while it was not the case. This has been confirmed with others. We will keep monitoring the situation closely.

Read the full incident report →

Minor February 5, 2026

Service Disruption

Detected by Pingoru: Feb 05, 2026, 01:48 PM UTC
Resolved: Feb 05, 2026, 01:48 PM UTC
Duration: —

Affected: IncomingTeam APISMTP RelaySending API

Timeline · 3 updates

identified Feb 05, 2026, 11:20 AM UTC

Status: Identified At approximately 12:20 PM (CET), we started receiving reports of infrastructure issues affecting our services. This is currently causing database connectivity problems, which may result in failed API requests or delays in email processing. Our team is actively investigating the issue. We will provide updates as soon as more information is available. Affected components Sending API (Partial outage) Team API (Partial outage) Outgoing (Transactional) (Partial outage) Incoming (Partial outage) SMTP Relay (Partial outage) Outgoing (Broadcast) (Partial outage)
monitoring Feb 05, 2026, 12:53 PM UTC

Status: Monitoring Our services have been restored and we are no longer seeing any issues. We are closely monitoring our infrastructure to ensure everything remains stable. Once this incident is fully resolved, we will publish a post-mortem with a detailed overview of what happened and what steps we are taking to prevent this in the future. Affected components Sending API (Operational) Team API (Operational) Outgoing (Transactional) (Operational) Incoming (Operational) SMTP Relay (Operational) Outgoing (Broadcast) (Operational)
resolved Feb 05, 2026, 01:48 PM UTC

Status: Resolved We have confirmed everything is stable again and are working with our upstream provider to work out the final details. As part of our post-incident process we are working on resolving any individual issues that might still have occurred. Do reach out to support if you have any questions. Our sincere apologies for the inconvenience. A post-mortem will be shared as soon as possible. Affected components SMTP Relay (Operational) Outgoing (Broadcast) (Operational) Sending API (Operational) Team API (Operational) Outgoing (Transactional) (Operational) Incoming (Operational)