SparkPost Outage History

Started Oct 11, 2026, 05:51 PM UTC· resolved Oct 11, 2026, 08:57 PM UTC

1. identified Oct 11, 2026, 05:51 PM UTC

   We are investigating an increase in delayed (deferred) messages in both our US and EU regions, beginning at approximately 14:40 UTC on October 11. A subset of our internal DNS resolvers are intermittently failing to resolve recipient domains, causing some delivery attempts to be temporarily deferred. Affected messages are not being dropped or bounced. Retries are succeeding as they are routed to healthy resolvers, so impacted messages are being delivered with additional latency. Customers may observe an elevated number of delay events in webhooks, event logs, and reporting during this time. We have identified the cause as a DNSSEC validation issue on a portion of our resolver fleet related to a scheduled update of the internet's root DNS signing key, and are applying a fix. No action is required from customers. We will provide an update within 60 minutes or as soon as we have more information.

2. identified Oct 11, 2026, 06:09 PM UTC

   We are continuing to rollout the new root signing keys from ICANN. We continue to see recovery across our global clusters.

3. identified Oct 11, 2026, 06:17 PM UTC

   We are continuing to work on a fix for this issue.

4. monitoring Oct 11, 2026, 06:17 PM UTC

   A fix has been implemented and we are monitoring the results.

5. resolved Oct 11, 2026, 08:57 PM UTC

   This incident has been resolved.

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Started Oct 01, 2026, 05:05 PM UTC· resolved Oct 01, 2026, 05:36 PM UTC

1. investigating Oct 01, 2026, 05:05 PM UTC

   Some email deliveries are being delayed. The delays come and go, and queued messages are being delivered once each one clears. Our team is investigating the cause and working on a fix. We'll post an update here as soon as we know more. We apologize for the disruption.

2. monitoring Oct 01, 2026, 05:16 PM UTC

   We've made changes to address the intermittent delivery delays. Since then, email has been delivered without delay, including during peak sending periods that previously caused the slowdowns. We're watching closely to confirm the issue is fully resolved and will post an update here. Thank you for your patience.

3. resolved Oct 01, 2026, 05:36 PM UTC

   This issue has been resolved. Since our changes went in, we've seen no further delivery delays, including through peak sending periods. Email is being delivered normally. We apologize for the disruption and thank you for your patience.

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Started Sep 17, 2026, 09:06 AM UTC· resolved Sep 17, 2026, 10:00 AM UTC

1. investigating Sep 17, 2026, 09:06 AM UTC

   We are investigating an increase in delivery latency for some outbound messages. (NOTE: This does not impact our customers hosted in the EU.)

2. monitoring Sep 17, 2026, 09:47 AM UTC

   A fix has been implemented and we are monitoring the results.

3. resolved Sep 17, 2026, 10:00 AM UTC

   This incident has been resolved.

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Started Sep 14, 2026, 02:19 PM UTC· resolved Sep 14, 2026, 04:46 PM UTC

1. investigating Sep 14, 2026, 02:19 PM UTC

   Health score and Cohort data is delayed.

2. identified Sep 14, 2026, 02:59 PM UTC

   We know what has caused the data delay and are working to get the data posted.

3. monitoring Sep 14, 2026, 04:31 PM UTC

   Data is reprocessed and loads are completing. Full data recovery expected in the next 30 minutes.

4. resolved Sep 14, 2026, 04:46 PM UTC

   The data has all been posted. We apologize for the delay.

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Started Aug 27, 2026, 04:51 PM UTC· resolved Aug 27, 2026, 10:56 PM UTC

1. identified Aug 27, 2026, 04:51 PM UTC

   Beginning 2026-08-26 around 23:00 UTC, we are observing a significant increase in hard bounces for messages sent to recipients at privaterelay.appleid.com, the relay domain used by Sign in with Apple. Affected messages are rejected by Apple's mail servers with the SMTP response 550 5.1.1 user not found. Our investigation confirms this originates upstream at the receiving mailbox provider, not within our platform. Delivery to all other domains, including icloud.com, me.com, and mac.com, remain unaffected and are performing normally. A substantial share of the affected addresses delivered successfully as recently as 2026-08-26, indicating the rejections do not reflect genuine invalid recipients. Impact: Because these are hard bounces, affected recipient addresses may be automatically added to your suppression list, which will prevent future sends to those recipients even after the underlying issue is resolved. Action required: None at this time. We recommend you do not attempt to manually clean or re-import affected suppression entries while the issue is ongoing. We are working directly with Apple on a resolution. Once resolved, we will remove suppression entries created by this event and will confirm the scope and timing in a follow-up update. We will post our next update within 4 hours or sooner if the situation changes.

2. identified Aug 27, 2026, 06:03 PM UTC

   We continue to see elevated 550 5.1.1 user not found hard bounces from Apple private relay. Once resolved on the provider's side, we will automatically remove Apple Private Relay suppression entries created by this event.

3. identified Aug 27, 2026, 07:10 PM UTC

   We have started to see recovery of the Apple private relay domain. We will continue monitoring for the next 60 minutes to confirm full recovery. Our team is actively working on automatically removing any suppressions that were created by this event. We anticipate the cleanup to be completed by 4PM EDT.

4. monitoring Aug 27, 2026, 07:28 PM UTC

   We have seen recovery of the Apple private relay domain to pre-event bounce levels. Our team is actively working on automatically removing any suppressions that were created by this event. We anticipate the cleanup to be completed by 6PM EDT.

5. resolved Aug 27, 2026, 10:56 PM UTC

   The Apple bounce levels have maintained at pre incident levels during our monitoring phase. Our clean up of the bad suppressions has finished. This incident is resolved.

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Started Aug 19, 2026, 06:52 PM UTC· resolved Aug 19, 2026, 07:58 PM UTC

1. investigating Aug 19, 2026, 06:52 PM UTC

   We are investigating an increase in delivery latency for some outbound messages. (NOTE: This does not impact our customers hosted in the US.)

2. monitoring Aug 19, 2026, 07:44 PM UTC

   A fix has been implemented and we are monitoring the results.

3. resolved Aug 19, 2026, 07:58 PM UTC

   This incident has been resolved.

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Started Jul 24, 2026, 11:14 AM UTC· resolved Jul 24, 2026, 06:44 PM UTC

1. investigating Jul 24, 2026, 11:14 AM UTC

   We are investigating delivery issues caused by an ongoing AWS US West 2 region outage. Customers may experience delays or failures while we assess the impact to our service. We are actively monitoring the situation and will provide updates as more information becomes available.

2. identified Jul 24, 2026, 11:53 AM UTC

   Outbound email delivery is blocked for our US West region. We working with our vendor resolve the issue. We are continuing to accept emails and queue them internally. We will deliver the messages as soon as the issue is resolved.

3. monitoring Jul 24, 2026, 12:08 PM UTC

   We are starting to deliver mails in our US West region. We are working through the queued messages. We are continuing to monitor the issue and continuing to accept emails.

4. monitoring Jul 24, 2026, 01:16 PM UTC

   We are still working through the queued messages. We are continuing to monitor the issue and continuing to accept emails.

5. monitoring Jul 24, 2026, 05:29 PM UTC

   We have implemented additional tuning to handle the significant influx of mail due to the AWS network outage and we are seeing improvement in delivery rates We are seeing significant recovery and expect most mail to be fully delivered in the next 30-35 minutes. Estimated time for full recovery is 80-90 minutes. We are continuing to look for additional optimizations and monitor the issue.

6. resolved Jul 24, 2026, 06:44 PM UTC

   This incident has been resolved.

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Started Jun 29, 2026, 03:58 PM UTC· resolved Jun 29, 2026, 04:46 PM UTC

1. investigating Jun 29, 2026, 03:58 PM UTC

   We are investigating the delay and the impact. We will post once we know more.

2. monitoring Jun 29, 2026, 04:05 PM UTC

   There was a combination of events that caused a short period of slowdown. That slowdown has already recovered and we are monitoring to ensure we do not see it again.

3. resolved Jun 29, 2026, 04:46 PM UTC

   This incident has been resolved.

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Started May 12, 2026, 12:48 PM UTC· resolved May 12, 2026, 01:38 PM UTC

1. identified May 12, 2026, 12:48 PM UTC

   We’re currently investigating an issue that prevented some customers from updating their payment details. The root cause has been identified, and a fix is being implemented.

2. monitoring May 12, 2026, 01:10 PM UTC

   A fix has been implemented and we are monitoring the results.

3. resolved May 12, 2026, 01:38 PM UTC

   This incident has been resolved.

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Started May 11, 2026, 06:55 PM UTC· resolved May 11, 2026, 08:02 PM UTC

1. identified May 11, 2026, 06:55 PM UTC

   We are experiencing an elevated level of errors and latency on the Suppression List API for some SparkPost customers. Please retry any 5xx error. Note: This issue does not impact SparkPost customers hosted in the EU.

2. monitoring May 11, 2026, 07:46 PM UTC

   A fix has been implemented and we are monitoring the results.

3. resolved May 11, 2026, 08:02 PM UTC

   This incident has been resolved.

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Started May 09, 2026, 09:39 PM UTC· resolved May 09, 2026, 10:17 PM UTC

1. investigating May 09, 2026, 09:39 PM UTC

   We are looking into why some messages are seeing delayed delivery.

2. identified May 09, 2026, 09:50 PM UTC

   The issue has been identified and a fix is being implemented.

3. monitoring May 09, 2026, 10:05 PM UTC

   A fix has been implemented and we are monitoring the results.

4. resolved May 09, 2026, 10:17 PM UTC

   This incident has been resolved.

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Started May 07, 2026, 09:31 AM UTC· resolved May 08, 2026, 11:31 AM UTC

1. investigating May 07, 2026, 09:31 AM UTC

   We are currently investigating this issue.

2. monitoring May 07, 2026, 10:49 AM UTC

   A fix has been implemented and we are monitoring the results.

3. resolved May 08, 2026, 11:31 AM UTC

   This incident has been resolved.

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Started Apr 05, 2026, 05:02 PM UTC· resolved Apr 05, 2026, 07:01 PM UTC

1. investigating Apr 05, 2026, 05:02 PM UTC

   We are currently investigating reports of delayed or failed email deliveries to Apple-hosted domains. Messages to non-Apple domains are unaffected. We will provide updates as more information becomes available.

2. identified Apr 05, 2026, 05:58 PM UTC

   The issue was caused by an Apple iCloud Mail outage (https://www.apple.com/support/systemstatus/), which Apple has since marked as resolved. Bounce rates and delivery delays to Apple domains have returned to normal levels. We are currently reviewing our suppression lists to identify and remove any recipients that may have been incorrectly added during the incident.

3. monitoring Apr 05, 2026, 06:27 PM UTC

   Apple has implemented a fix and we are monitoring the results.

4. resolved Apr 05, 2026, 07:01 PM UTC

   Delivery rates to Apple domains have returned to normal with no further elevated delays or bounces. We will perform any necessary post-incident cleanup of suppression lists to ensure no recipients were incorrectly suppressed during the outage. NOTE: As of Monday April 5th at 9PM EDT the cleanup has been completed. All recipient addresses to Apple or Apple Private Relay domains that were suppressed during Apple's incident window were removed.

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Started Mar 12, 2026, 06:51 AM UTC· resolved Mar 12, 2026, 11:25 AM UTC

1. investigating Mar 12, 2026, 06:51 AM UTC

   We are currently investigating issues with delivery of email impacting US region.

2. monitoring Mar 12, 2026, 07:48 AM UTC

   System is fully recovered and under monitoring.

3. investigating Mar 12, 2026, 08:00 AM UTC

   Email delivery in US is impacted, experiencing elevated delays.

4. monitoring Mar 12, 2026, 10:03 AM UTC

   System functionality has been fully restored and all emails are being transmitted correctly without added latencies; we are actively monitoring.

5. resolved Mar 12, 2026, 11:25 AM UTC

   This incident has been resolved.

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Started Mar 05, 2026, 12:51 AM UTC· resolved Mar 05, 2026, 01:24 AM UTC

1. investigating Mar 05, 2026, 12:51 AM UTC

   We are investigating an increase in delivery latency for some outbound messages.

2. monitoring Mar 05, 2026, 01:00 AM UTC

   We are observing recovery in email delivery performance and are actively monitoring.

3. resolved Mar 05, 2026, 01:24 AM UTC

   This incident has been resolved.

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Started Feb 26, 2026, 05:55 PM UTC· resolved Feb 27, 2026, 05:38 PM UTC

1. monitoring Feb 26, 2026, 05:55 PM UTC

   We are currently seeing elevated temporary rejection rates for email delivered to Outlook.com, Hotmail, and other Microsoft-hosted addresses. Microsoft has acknowledged the issue and is actively investigating. This is a industry-wide issue and not isolated to any specific account. We will continue to monitor and update this page as we receive more information. Next update: When Microsoft posts a resolution or Bird observes delivery rates normalizing

2. resolved Feb 27, 2026, 05:38 PM UTC

   Microsoft has confirmed that they made additional changes the night of Thursday, Feb 26th that should have remediated most IP rate limiting and rejection issues. If you are still seeing impacts, please reach out via your normal support channels and our team can investigate and escalate with Microsoft.

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Started Feb 24, 2026, 07:07 PM UTC· resolved Feb 24, 2026, 07:41 PM UTC

1. investigating Feb 24, 2026, 07:07 PM UTC

   We are experiencing an elevated level of errors and latency on the Transmissions API (injection API) for some SparkPost customers. Please retry any 5xx error. Note: This issue does not impact SparkPost customers hosted in the EU.

2. investigating Feb 24, 2026, 07:07 PM UTC

   We are continuing to investigate this issue.

3. investigating Feb 24, 2026, 07:25 PM UTC

   We are continuing to investigate this issue. We still see 5xx errors on mail injections and degradation.

4. identified Feb 24, 2026, 07:34 PM UTC

   The team has identified the root cause. There is a core networking issue that has impacted sending across the clusters.

5. monitoring Feb 24, 2026, 07:38 PM UTC

   A fix has been implemented and we are monitoring the results.

6. resolved Feb 24, 2026, 07:41 PM UTC

   This incident has been resolved.

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Started Jan 27, 2026, 04:39 PM UTC· resolved Feb 05, 2026, 12:22 PM UTC

1. identified Jan 27, 2026, 04:39 PM UTC

   We have identified an issue affecting Single Sign-On (SSO) logins. Users authenticating via SSO are unable to access their accounts. A fix has been deployed and we expect the issue to be resolved within the next few minutes. We apologize for the inconvenience and will provide an update shortly.

2. monitoring Jan 27, 2026, 04:41 PM UTC

   A fix has been implemented and we are monitoring the results.

3. resolved Feb 05, 2026, 12:22 PM UTC

   This incident has been resolved.

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Started Jan 15, 2026, 10:24 AM UTC· resolved Jan 27, 2026, 04:33 PM UTC

1. investigating Jan 15, 2026, 10:24 AM UTC

   We are currently investing reported delays when sending emails towards Microsoft email domains

2. investigating Jan 15, 2026, 11:06 AM UTC

   Impact is currently scoped to EU region only. Investigation ongoing; tickets raised to Microsoft to further investigation.

3. investigating Jan 15, 2026, 11:13 AM UTC

   We continue to work with Microsoft on full mitigation. They are currently experiencing infrastructure issues that is causing them to incorrectly block legitimate traffic from multiple Bird IP ranges. Our sending infrastructure and email traffic are operating normally. All other mailbox providers are receiving mail without issue. Microsoft is aware of the issue and is actively investigating. We are in contact with their team and monitoring for resolution. We expect this to be resolved once Microsoft completes their fix. Messages will retry automatically - no action needed from you

4. investigating Jan 15, 2026, 11:50 AM UTC

   Microsoft continues to investigate the issue. We are actively in contact with their team.

5. identified Jan 15, 2026, 01:25 PM UTC

   We continue to work with Microsoft on these delays. We are in active contact with their delivery team and working towards full resolution.

6. identified Jan 15, 2026, 01:49 PM UTC

   We have started to receive reports from Microsoft that they are implementing mitigations within their environment. We continue to monitor and coordinate with them for full resolution.

7. identified Jan 16, 2026, 04:03 PM UTC

   We continue to see some delays at Microsoft domains and are working with Microsoft to remediate. At this time, Microsoft is aware and continues to investigate.

8. monitoring Jan 17, 2026, 11:30 PM UTC

   We have seen stabilization, but are still seeing Microsoft delays in rare cases. Our team is mitigating with Microsoft as those occur. We are going to keep the status page in Monitoring state through the weekend as we continue to monitor for a full recovery at Microsoft.

9. monitoring Jan 19, 2026, 06:18 PM UTC

   We continue to see improvement with Microsoft delivery, though isolated cases of delays persist. Microsoft's mitigations are largely effective, but we're still working with their team to address edge cases as they arise. We will continue to maintain heightened monitoring through the week to ensure complete stabilization. No action is required from senders - any affected messages will continue to retry automatically.

10. monitoring Jan 23, 2026, 05:11 AM UTC

    We continue to receive reports of outages at Microsoft, as well as delayed mail sending to Microsoft and their related properties. If you are experiencing delays or IP blocks in sending to Microsoft related properties, please open a ticket with your Technical Account Manager or email [email protected] (or your dedicated support channel if applicable). For detals around the Microsoft 365 please reference Microsoft's Status Page at: https://status.cloud.microsoft/m365

11. resolved Jan 27, 2026, 04:33 PM UTC

    We continue to receive sporadic reports of outages at Microsoft, as well as delayed mail sending to Microsoft and their related properties. But have seen recovery for most senders. If you are experiencing delays or IP blocks in sending to Microsoft related properties, please open a ticket with your Technical Account Manager or email [email protected] (or your dedicated support channel if applicable).

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Started Jan 14, 2026, 01:00 PM UTC· resolved Jan 14, 2026, 01:00 PM UTC

1. resolved Jan 14, 2026, 04:27 PM UTC

   We've experienced processing delays of up to 1h30min for sending emails to yahoo.com domain in the EU and US regions.

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Started Dec 11, 2025, 06:36 PM UTC· resolved Dec 11, 2025, 10:28 PM UTC

1. investigating Dec 11, 2025, 06:36 PM UTC

   There is a delay in our events pipeline. This is causing metrics, events and webhooks to be delayed for a portion of data. Message sending is not effected.

2. monitoring Dec 11, 2025, 10:18 PM UTC

   A fix has been implemented and we are monitoring the results.

3. resolved Dec 11, 2025, 10:28 PM UTC

   This incident has been resolved.

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Started Dec 11, 2025, 04:34 PM UTC· resolved Dec 11, 2025, 06:34 PM UTC

1. investigating Dec 11, 2025, 04:34 PM UTC

   Messages that have failed initial delivery and are in a delayed state are taking longer than expected to resend. Only messages injected via SMTP and in a delayed state are effected.

2. identified Dec 11, 2025, 04:57 PM UTC

   The issue has been identified and the fix has been deployed.

3. monitoring Dec 11, 2025, 05:00 PM UTC

   A fix has been implemented and we are monitoring the results.

4. resolved Dec 11, 2025, 06:34 PM UTC

   This incident has been resolved.

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Started Dec 10, 2025, 09:22 PM UTC· resolved Dec 11, 2025, 12:32 AM UTC

1. investigating Dec 10, 2025, 09:22 PM UTC

   We are currently looking into a data delay. This is causing our metrics to be delayed. It is not effecting mail sending.

2. monitoring Dec 11, 2025, 12:23 AM UTC

   Our pipeline that was having issue has recovered. We are monitoring to ensure we stay in a good state. Very sorry for the inconvenience.

3. resolved Dec 11, 2025, 12:32 AM UTC

   This incident has been resolved.

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Started Dec 10, 2025, 03:40 AM UTC· resolved Dec 10, 2025, 06:09 AM UTC

1. investigating Dec 10, 2025, 03:40 AM UTC

   We are looking into increased error rates and high latency across our APIs. This could be related to a third party outage.

2. monitoring Dec 10, 2025, 04:46 AM UTC

   One of our third party providers is experiencing increased latency. This is causing a very small amount of the traffic hitting our APIs to error or have high latency. We are monitoring to ensure the latency and error rates don't increase while waiting for their team to resolve the issue.

3. resolved Dec 10, 2025, 06:09 AM UTC

   This incident has been resolved.

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Started Dec 08, 2025, 02:24 AM UTC· resolved Dec 08, 2025, 05:33 AM UTC

1. investigating Dec 08, 2025, 02:24 AM UTC

   Our data processing services are running behind; some customers may see a delay of data available via the: - SparkPost App (webUI): Signals Reports - Events API - Metrics API Message injection and outbound message delivery are not impacted - all messages are flowing as expected.

2. identified Dec 08, 2025, 03:21 AM UTC

   The issue has been identified and a fix is being implemented.

3. identified Dec 08, 2025, 04:26 AM UTC

   We have been able to catch up all data from the 5th and are working on the 6th now.

4. identified Dec 08, 2025, 04:51 AM UTC

   We are continuing to work on a fix for this issue.

5. resolved Dec 08, 2025, 05:33 AM UTC

   This incident has been resolved.

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