OneSignal outage: Intermittent errors on /api/v1/notifications api

1. resolvedSep 18, 2026, 01:23 UTC

   /api/v1/notifications create endpoint is now stable for all customers. The team has scaled up resources to handle increased load on our notifications service.

2. identifiedSep 18, 2026, 01:13 UTC

   A fix is rolling out now for the affected notifications services that are overloaded. Things should be stable within the next 10 minutes.

3. identifiedSep 18, 2026, 00:48 UTC

   We have identified the root cause and are working towards a resolution. Heavy load on one of our notification services is causing intermittent errors when trying to create a notification. Not all customers are affected. The team is working on adding more capacity to the affected service. We will provide another update in 15 minutes.

What APIStatus.watch saw

• Sep 18, 2026, 00:50 UTCoperational → partial outage
• Sep 18, 2026, 01:25 UTCpartial outage → operational

Other services with incidents at the same time

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How often does OneSignal have incidents?

OneSignal reported 9 incidents in the last 90 days, 3 of them major or critical. A typical incident lasted 1h 29m. See OneSignal's uptime and incident history