Emerging
Jun 18, 2026 Major2
83%
Anthropic's Claude AI Service Experiences Widespread Outage on June 18
Anthropic's Claude AI service experienced a major outage on June 18, 2026, with over 2,500 complaints recorded on Downdetector. Users reported widespread access issues across Claude Chat, app, website, and login services. While the company implemented a fix, certain models including Opus 4.8 continued to experience elevated error rates.
Quick Facts
Who
Anthropic
What
Claude AI service outage
When
June 18, 2026
Where
Claude web interface
- Claude AI service outage
- elevated error rates across multiple models
- service disruption affecting web interface, API, Claude Code, and Claude Cowork
- Anthropic implemented a fix
- persistent errors on Opus 4.8 and Haiku 4.5 models
Anthropic's Claude AI service experienced a significant outage on June 18, 2026, affecting users across multiple platforms and services. Beginning around midday, the service disruption prompted over 2,500 complaints on outage-tracking platform Downdetector within hours. Users reported widespread issues accessing Claude Chat, the mobile app, website, API, and login services, with Claude Chat accounting for approximately 60% of reported problems. Some users experienced failed conversations, error messages when submitting prompts, and inability to sign in to their accounts.
Anthropic's status page indicated the company was investigating elevated error rates affecting numerous models and the Claude web interface, API, Claude Code, and Claude Cowork services. The company reported that all Sonnet and Opus models experienced error rates of approximately 10% during the initial half-hour of the outage. Opus 4.8 was particularly impacted, sustaining an average error rate of 10% for approximately one hour and 20 minutes following the resolution of issues affecting other models.
The company implemented a fix and reported the issue resolved around 2 p.m. ET, with Downdetector reports dropping from a peak of over 2,100 to 518 within 15 minutes. However, subsequent updates indicated that Anthropic continued to see errors with Claude Opus 4.8 and Haiku 4.5 models as the outage developed. The company stated it was monitoring results and working toward a complete resolution but did not provide specific details about the root cause or an estimated timeline for full service restoration across all affected models.
This outage comes amid broader developments at Anthropic, including recent government export control restrictions on the company's Fable 5 model. The June 18 service disruption was one of the largest outages reported for the Claude platform, affecting the chatbot's availability during a critical period of user activity.
Why This Matters
This outage highlights the critical infrastructure risks in AI service delivery and the operational challenges that even leading AI companies face at scale. For business users relying on Claude for customer service, content creation, and development workflows, the widespread nature of this disruption—affecting chat, API, and code services simultaneously—underscores the importance of redundancy and failover planning. The persistence of errors on premium Opus models after the initial fix also suggests underlying architectural issues that could impact enterprise SLAs and user confidence in AI service reliability.
Timeline & Sources
Jun 18, 2026
WireDowndetector reports cross 2,500 as outage complaints spike
Jun 18, 2026
WirePeak of outage reports reaches 2,103 on Downdetector
Jun 18, 2026
WireAnthropic's status page reports issue and begins investigating elevated errors
Jun 18, 2026
WireDowndetector reports drop to 518 as initial fix appears to take effect
Jun 18, 2026
WireAnthropic announces it has implemented a fix and is monitoring results
Jun 18, 2026
WireAnthropic reports Opus 4.8 continues experiencing errors despite initial fix