Haiku 4.5 errors under investigation; Opus 4.5 incident resolved

Anthropic is investigating elevated errors on Haiku 4.5 (Jul 20, 13:20 UTC). The Opus 4.5 incident from earlier that day has been resolved. A previous Claude Sonnet 5 incident (Jul 16) has also been removed from the status history.

Jul 20, 2026Views:0

Impact Assessment

Cost0

Reliability3

Migration0

Quality1

Compliance0

Haiku 4.5 errors may cause degraded performance for users; Opus 4.5 is now stable. No cost or migration impact.

Changes

Before

Elevated error rates for Opus 4.5 | https://status.claude.com/incidents/hlt0yqp4lkww | &lt;p&gt; &lt;small&gt;Jul &lt;var data-var=&apos;date&apos;&gt;20&lt;/var&gt;, &lt;var data-var=&apos;time&apos;&gt;10:57&lt;/var&gt; UTC&lt;/small&gt;&lt;br&gt; &lt;strong&gt;Monitoring&lt;/strong&gt; - A fix has been implemented and we are monitoring the results. &lt;/p&gt; &lt;p&gt; &lt;small&gt;Jul &lt;var data-var=&apos;date&apos;&gt;20&lt;/var&gt;, &lt;var data-var=&apos;time&apos;&gt;10:05&lt;/var&gt; UTC&lt;/small&gt;&lt;br&gt; &lt;strong&gt;Update&lt;/strong&gt; - We are continuing to work on a fix for this issue. &lt;/p&gt; &lt;p&gt; &lt;small&gt;Jul &lt;var data-var=&apos;date&apos;&gt;20&lt;/var&gt;, &lt;var data-var=&apos;time&apos;&gt;07:57&lt;/var&gt; UTC&lt;/small&gt;&lt;br&gt; &lt;strong&gt;Identified&lt;/strong&gt; - The issue has been identified and a fix is being implemented. &lt;/p&gt; &lt;p&gt; &lt;small&gt;Jul &lt;var data-var=&apos;date&apos;&gt;20&lt;/var&gt;, &lt;var data-var=&apos;time&apos;&gt;07:03&lt;/var&gt; UTC&lt;/small&gt;&lt;br&gt; &lt;strong&gt;Investigating&lt;/strong&gt; - We are currently investigating this issue. &lt;/p&gt;
Elevated errors on Claude Sonnet 5 | https://status.claude.com/incidents/30x7lsq713tl | &lt;p&gt; &lt;small&gt;Jul &lt;var data-var=&apos;date&apos;&gt;16&lt;/var&gt;, &lt;var data-var=&apos;time&apos;&gt;08:53&lt;/var&gt; UTC&lt;/small&gt;&lt;br&gt; &lt;strong&gt;Resolved&lt;/strong&gt; - This incident has been resolved. &lt;/p&gt; &lt;p&gt; &lt;small&gt;Jul &lt;var data-var=&apos;date&apos;&gt;16&lt;/var&gt;, &lt;var data-var=&apos;time&apos;&gt;08:39&lt;/var&gt; UTC&lt;/small&gt;&lt;br&gt; &lt;strong&gt;Investigating&lt;/strong&gt; - We are currently investigating this issue. &lt;/p&gt;

After

Elevated errors on Haiku 4.5 | https://status.claude.com/incidents/s39rkbp2xhpd | &lt;p&gt; &lt;small&gt;Jul &lt;var data-var=&apos;date&apos;&gt;20&lt;/var&gt;, &lt;var data-var=&apos;time&apos;&gt;13:20&lt;/var&gt; UTC&lt;/small&gt;&lt;br&gt; &lt;strong&gt;Investigating&lt;/strong&gt; - We are currently investigating this issue. &lt;/p&gt;
Elevated error rates for Opus 4.5 | https://status.claude.com/incidents/hlt0yqp4lkww | &lt;p&gt; &lt;small&gt;Jul &lt;var data-var=&apos;date&apos;&gt;20&lt;/var&gt;, &lt;var data-var=&apos;time&apos;&gt;12:48&lt;/var&gt; UTC&lt;/small&gt;&lt;br&gt; &lt;strong&gt;Resolved&lt;/strong&gt; - This incident has been resolved. &lt;/p&gt; &lt;p&gt; &lt;small&gt;Jul &lt;var data-var=&apos;date&apos;&gt;20&lt;/var&gt;, &lt;var data-var=&apos;time&apos;&gt;10:57&lt;/var&gt; UTC&lt;/small&gt;&lt;br&gt; &lt;strong&gt;Monitoring&lt;/strong&gt; - A fix has been implemented and we are monitoring the results. &lt;/p&gt; &lt;p&gt; &lt;small&gt;Jul &lt;var data-var=&apos;date&apos;&gt;20&lt;/var&gt;, &lt;var data-var=&apos;time&apos;&gt;10:05&lt;/var&gt; UTC&lt;/small&gt;&lt;br&gt; &lt;strong&gt;Update&lt;/strong&gt; - We are continuing to work on a fix for this issue. &lt;/p&gt; &lt;p&gt; &lt;small&gt;Jul &lt;var data-var=&apos;date&apos;&gt;20&lt;/var&gt;, &lt;var data-var=&apos;time&apos;&gt;07:57&lt;/var&gt; UTC&lt;/small&gt;&lt;br&gt; &lt;strong&gt;Identified&lt;/strong&gt; - The issue has been identified and a fix is being implemented. &lt;/p&gt; &lt;p&gt; &lt;small&gt;Jul &lt;var data-var=&apos;date&apos;&gt;20&lt;/var&gt;, &lt;var data-var=&apos;time&apos;&gt;07:03&lt;/var&gt; UTC&lt;/small&gt;&lt;br&gt; &lt;strong&gt;Investigating&lt;/strong&gt; - We are currently investigating this issue. &lt;/p&gt;

Sources

status

Anthropic Status History

Elevated errors on Haiku 4.5 | https://status.claude.com/incidents/s39rkbp2xhpd | <p> <small>Jul <var data-var='date'>20</var>, <var data-var='time'&g...

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