Outage in Anthropic
Elevated errors on Sonnet 4, Sonnet 4.5 and Haiku 4.5
Resolved MajorIncident Report
We are currently investigating this issue.
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Latest Updates ( sorted recent to last )
RESOLVED
5 days ago - at 11/20/2025 12:03PM
As of 3:55 PT / 11:55 UTC the level of errors on Sonnet 4.0 has returned to normal.
MONITORING
5 days ago - at 11/20/2025 11:03AM
As of 2:14 PT / 10:14 UTC we have mitigated all errors on Sonnet 4.5. Unfortunately the error rate is still higher than baseline for Sonnet 4.0, but we have implemented a fix and it should go down in the next few minutes.
IDENTIFIED
5 days ago - at 11/20/2025 10:15AM
We are continuing to work on a fix for this issue.
IDENTIFIED
5 days ago - at 11/20/2025 09:10AM
The issue has been identified and a fix is being implemented.
INVESTIGATING
5 days ago - at 11/20/2025 08:20AM
We are continuing to investigate this issue.
INVESTIGATING
5 days ago - at 11/20/2025 08:10AM
We are currently investigating this issue.
Latest Anthropic outages
Model usage attribution issues - about 7 hours ago
Elevated error rates on the API - 1 day ago
Increased error rate on Claude 4 Sonnet - 6 days ago
Elevated errors on claude.ai - 7 days ago
Elevated error rates to Sonnet 4.5 on Claude Code - 7 days ago
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