# Anthropic in September 2026: incidents, uptime and changes > Anthropic in September 2026: 13 incidents on its status page (8 major or critical), 84.96% free of major or critical incidents (vendor-reported), 1 CVE. From Rewindex’s archive of Anthropic’s status, pricing and policy pages. Canonical: https://rewindex.com/company/anthropic/2026/09 Last updated: 2026-10-01T00:00:00Z - Incidents posted: 13 (major/critical: 8) · Maintenance: 0 - By vendor impact label: major 8, minor 4, none 1 - Uptime (vendor-reported): 84.96% free of major/critical incidents, 84.50% free of any incident; outage time 4.5 days, incident time 4.6 days - Price changes: 0 · Pricing/legal/trust page changes: 0 · Deprecations: 0 · CVEs: 1 - Previous month: [August 2026](https://rewindex.com/company/anthropic/2026/08.md) · Next: [October 2026](https://rewindex.com/company/anthropic/2026/10.md) · [All months](https://rewindex.com/company/anthropic/reports.md) · [Anthropic](https://rewindex.com/company/anthropic.md) _Uptime: Derived from the incidents the vendor posted on its own status page, not measured by us. A minute counts as an outage minute when a major or critical incident (as the vendor labelled it) was open; incident minutes include minor ones too. Maintenance and incidents marked "no impact" are left out, overlapping incidents are merged, a resolved incident counts for at most 7 days, and one still open with no resolution counts for at most 24 hours._ ## Major and critical incidents | Incident | Impact (vendor label) | Started (UTC) | Resolved (UTC) | Duration | Status | | --- | --- | --- | --- | --- | --- | | [Elevated errors for Claude Sonnet 5](https://rewindex.com/company/anthropic/incidents/ls6bn1x81m0w.md) | major | 2026-09-02 21:17 UTC | 2026-09-02 21:44 UTC | 26 min | resolved | | [Elevated errors for Claude Sonnet 5](https://rewindex.com/company/anthropic/incidents/288w7p4hk1l1.md) | major | 2026-09-03 12:37 UTC | 2026-09-03 12:56 UTC | 19 min | resolved | | [Elevated errors for multiple models](https://rewindex.com/company/anthropic/incidents/461yvfrzpwtt.md) | major | 2026-09-03 13:26 UTC | 2026-09-03 16:23 UTC | 3.0 h | resolved | | [Degraded functionality for Claude Cowork on Windows](https://rewindex.com/company/anthropic/incidents/r1pqn1kb4hvk.md) | major | 2026-09-10 15:54 UTC | 2026-09-14 19:14 UTC | 4 d | resolved | | [Elevated errors for Claude Mythos 5.1 and Claude Fable 5.1](https://rewindex.com/company/anthropic/incidents/t33dncr5ydvl.md) | major | 2026-09-11 14:19 UTC | 2026-09-11 14:37 UTC | 17 min | resolved | | [Intermittent error spikes for Claude Mythos 5.1 and Claude Fable 5.1](https://rewindex.com/company/anthropic/incidents/6304r9jjhj34.md) | major | 2026-09-15 09:48 UTC | 2026-09-15 11:14 UTC | 1.4 h | resolved | | [Elevated errors for multiple models](https://rewindex.com/company/anthropic/incidents/7g1qpkyz5gxh.md) | major | 2026-09-22 00:57 UTC | 2026-09-22 02:35 UTC | 1.6 h | resolved | | [Elevated errors on claude.ai, Claude Code, Claude Cowork and the Claude API](https://rewindex.com/company/anthropic/incidents/4xvtc2gnq73l.md) | major | 2026-09-29 14:21 UTC | 2026-09-29 16:27 UTC | 2.1 h | resolved | ## All incidents | Incident | Impact (vendor label) | Started (UTC) | Resolved (UTC) | Duration | Status | | --- | --- | --- | --- | --- | --- | | [Degraded performance on Claude for Microsoft Office 365](https://rewindex.com/company/anthropic/incidents/nr3h7bw8b3k3.md) | minor | 2026-09-01 16:02 UTC | 2026-09-01 16:22 UTC | 20 min | resolved | | [Degraded performance on platform.claude.com and Claude for Microsoft Office 365](https://rewindex.com/company/anthropic/incidents/3g3d55q6vk3h.md) | minor | 2026-09-01 17:05 UTC | 2026-09-01 18:07 UTC | 1.0 h | resolved | | [Delays in credit purchases](https://rewindex.com/company/anthropic/incidents/620swtqyn24k.md) | minor | 2026-09-01 23:26 UTC | 2026-09-02 01:24 UTC | 2.0 h | resolved | | [Elevated errors for Claude Sonnet 5](https://rewindex.com/company/anthropic/incidents/ls6bn1x81m0w.md) | major | 2026-09-02 21:17 UTC | 2026-09-02 21:44 UTC | 26 min | resolved | | [Elevated errors for Claude Sonnet 5](https://rewindex.com/company/anthropic/incidents/288w7p4hk1l1.md) | major | 2026-09-03 12:37 UTC | 2026-09-03 12:56 UTC | 19 min | resolved | | [Elevated errors for multiple models](https://rewindex.com/company/anthropic/incidents/461yvfrzpwtt.md) | major | 2026-09-03 13:26 UTC | 2026-09-03 16:23 UTC | 3.0 h | resolved | | [Degraded functionality for Claude Cowork on Windows](https://rewindex.com/company/anthropic/incidents/r1pqn1kb4hvk.md) | major | 2026-09-10 15:54 UTC | 2026-09-14 19:14 UTC | 4 d | resolved | | [Elevated latency on the Claude API for some users](https://rewindex.com/company/anthropic/incidents/2pt83vlkk7x7.md) | minor | 2026-09-10 21:43 UTC | 2026-09-10 23:24 UTC | 1.7 h | resolved | | [Elevated errors for Claude Mythos 5.1 and Claude Fable 5.1](https://rewindex.com/company/anthropic/incidents/t33dncr5ydvl.md) | major | 2026-09-11 14:19 UTC | 2026-09-11 14:37 UTC | 17 min | resolved | | [Intermittent error spikes for Claude Mythos 5.1 and Claude Fable 5.1](https://rewindex.com/company/anthropic/incidents/6304r9jjhj34.md) | major | 2026-09-15 09:48 UTC | 2026-09-15 11:14 UTC | 1.4 h | resolved | | [Issues with Google Play subscriptions](https://rewindex.com/company/anthropic/incidents/t8fpw9vcshl9.md) | none | 2026-09-16 16:18 UTC | 2026-09-16 16:51 UTC | 33 min | resolved | | [Elevated errors for multiple models](https://rewindex.com/company/anthropic/incidents/7g1qpkyz5gxh.md) | major | 2026-09-22 00:57 UTC | 2026-09-22 02:35 UTC | 1.6 h | resolved | | [Elevated errors on claude.ai, Claude Code, Claude Cowork and the Claude API](https://rewindex.com/company/anthropic/incidents/4xvtc2gnq73l.md) | major | 2026-09-29 14:21 UTC | 2026-09-29 16:27 UTC | 2.1 h | resolved | ## CVEs published - [CVE-2026-103012](https://rewindex.com/cve/CVE-2026-103012.md) (CVSS 2.0), published 2026-09-30 ## Cite this Anthropic posted 13 status incidents in September 2026 (8 major or critical); 0 price changes and 0 notable page changes observed. - Canonical URL: https://rewindex.com/company/anthropic/2026/09 - Citation: Anthropic, “Anthropic in September 2026” (2026-09-01 00:00 UTC). Archived by Rewindex: https://rewindex.com/company/anthropic/2026/09 (CC BY 4.0). - Markdown link: `[Anthropic: Anthropic in September 2026 (2026-09-01)](https://rewindex.com/company/anthropic/2026/09)` --- Canonical: https://rewindex.com/company/anthropic/2026/09 · Markdown: https://rewindex.com/company/anthropic/2026/09.md · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-11-04T11:08:48.294Z