Anthropic outage: Elevated errors for Claude Sonnet 5.5 and other models

Affected components

• Claude API (api.anthropic.com)
• Claude Code
• Claude Cowork
• claude.ai

1. resolvedOct 25, 2026, 07:53 UTC

   The issue affecting Claude services has been resolved. Impact occurred from 23:05 PT on October 24 / 06:05 UTC on October 25 to 23:35 PT on October 24 / 06:35 UTC on October 25.

2. monitoringOct 25, 2026, 06:35 UTC

   A fix has been deployed for the issue affecting Claude services and we are monitoring for recovery.

3. identifiedOct 25, 2026, 06:27 UTC

   We have identified the cause of elevated errors on requests to Claude Sonnet 5.5 and are working on a fix. We will provide an update as soon as possible.

4. investigatingOct 25, 2026, 06:14 UTC

   We are investigating elevated errors on requests to Claude Mythos 5.1, Claude Fable 5.1, Claude Opus 5.5, Claude Sonnet 5.5, and Claude Haiku 5.5. We will provide an update as soon as possible.

What APIStatus.watch saw

• Oct 25, 2026, 06:18 UTCoperational → degraded
• Oct 25, 2026, 06:38 UTCdegraded → operational
• Oct 25, 2026, 08:19 UTCoperational → degraded
• Oct 25, 2026, 08:34 UTCdegraded → operational

Other services with incidents at the same time

Overlapping incidents aren't necessarily related.

• Snyk: Snyk Container Degradation in SNYK-US-01Major · Oct 22, 2026, 21:53 UTC
• Snyk: Snyk Test Down in SNYK-US-01Major · Oct 23, 2026, 14:10 UTC
• Twilio: Voice Call Post Dial Delay from a Subset of Twilio Phone Numbers to ThailandMinor · Oct 12, 2026, 11:53 UTC
• Twilio: SMS Delivery Delays and Failures from Twilio Short Codes to Multiple Networks in IndiaMinor · Oct 21, 2026, 16:32 UTC
• Supabase: Elevated Mgmt API Error Rates in Multiple RegionsMinor · Oct 22, 2026, 17:01 UTC
• Twilio: Voice Call Post Dial Delay from Twilio Phone Numbers to ChileMinor · Oct 23, 2026, 14:53 UTC
• Twilio: SMS Delivery Delays from Twilio to Claro Costa RicaMinor · Oct 24, 2026, 00:48 UTC
• Twilio: Voice Call Failures and Post Dial Delay From a Subset of Twilio Phone Numbers to United StatesMinor · Oct 24, 2026, 14:17 UTC
• Tailscale: Funnel hostnames not resolving in public DNSMinor · Oct 24, 2026, 17:23 UTC
• Twilio: Silent Network Authentication (SNA) Missing Redirects on Vodafone in United KingdomMinor · Oct 24, 2026, 18:42 UTC

How often does Anthropic have incidents?

Anthropic reported 53 incidents in the last 90 days, 27 of them major or critical. A typical incident lasted 1h 2m. See Anthropic's uptime and incident history