# Anthropic in December 2025: incidents, uptime and changes

> Anthropic in December 2025: 21 incidents on its status page (8 major or critical), 99.20% free of major or critical incidents (vendor-reported). From Rewindex’s archive of Anthropic’s status, pricing and policy pages.

Canonical: https://rewindex.com/company/anthropic/2025/12
Last updated: 2026-01-01T00:00:00Z

- Incidents posted: 21 (major/critical: 8) · Maintenance: 0
- By vendor impact label: critical 3, major 5, minor 11, none 2
- Uptime (vendor-reported): 99.20% free of major/critical incidents, 83.77% free of any incident; outage time 5 h 55 min, incident time 5.0 days
- Price changes: 0 · Pricing/legal/trust page changes: 0 · Deprecations: 0 · CVEs: 0
- Previous month: [November 2025](https://rewindex.com/company/anthropic/2025/11.md) · Next: [January 2026](https://rewindex.com/company/anthropic/2026/01.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 |
| --- | --- | --- | --- | --- | --- |
| [Claude.ai is unavailable](https://rewindex.com/company/anthropic/incidents/49cmvxrrk228.md) | critical | 2025-12-05 09:02 UTC | 2025-12-05 09:33 UTC | 31 min | resolved |
| [Elevated errors across many models](https://rewindex.com/company/anthropic/incidents/9g6qpr72ttbr.md) | critical | 2025-12-14 21:31 UTC | 2025-12-14 22:51 UTC | 1.3 h | resolved |
| [Cannot create new conversations on Claude.ai](https://rewindex.com/company/anthropic/incidents/2f7kwfs03p6v.md) | critical | 2025-12-16 16:23 UTC | 2025-12-16 16:43 UTC | 20 min | resolved |
| [Elevated errors on claude.ai](https://rewindex.com/company/anthropic/incidents/qj71q3gqvvlk.md) | major | 2025-12-02 16:34 UTC | 2025-12-02 18:07 UTC | 1.6 h | resolved |
| [Elevated errors on Claude Haiku 4.5 and Opus 4.5](https://rewindex.com/company/anthropic/incidents/47tkhrwf5pl5.md) | major | 2025-12-03 12:20 UTC | 2025-12-03 12:29 UTC | 9 min | resolved |
| [Claude.ai is unavailable](https://rewindex.com/company/anthropic/incidents/h183k7hqb9lk.md) | major | 2025-12-05 10:47 UTC | 2025-12-05 11:27 UTC | 40 min | resolved |
| [Unable to start chats on claude.ai](https://rewindex.com/company/anthropic/incidents/h140lstlzbw7.md) | major | 2025-12-12 08:00 UTC | 2025-12-12 08:00 UTC | 0 min | resolved |
| [New chats defaulting to Claude Opus](https://rewindex.com/company/anthropic/incidents/z9kwvvpg0hy0.md) | major | 2025-12-16 19:30 UTC | 2025-12-16 20:52 UTC | 1.4 h | resolved |

## All incidents

| Incident | Impact (vendor label) | Started (UTC) | Resolved (UTC) | Duration | Status |
| --- | --- | --- | --- | --- | --- |
| [Investigating reports of increased latency](https://rewindex.com/company/anthropic/incidents/2mkpsnk9nyg0.md) | minor | 2025-12-01 22:09 UTC | 2025-12-02 00:15 UTC | 2.1 h | resolved |
| [Elevated errors on claude.ai](https://rewindex.com/company/anthropic/incidents/qj71q3gqvvlk.md) | major | 2025-12-02 16:34 UTC | 2025-12-02 18:07 UTC | 1.6 h | resolved |
| [Elevated errors on Claude Haiku 4.5 and Opus 4.5](https://rewindex.com/company/anthropic/incidents/47tkhrwf5pl5.md) | major | 2025-12-03 12:20 UTC | 2025-12-03 12:29 UTC | 9 min | resolved |
| [Elevated Error Rates on Claude API Code Execution and Advanced File Analysis Tools](https://rewindex.com/company/anthropic/incidents/s8vj5mn9wvzf.md) | none | 2025-12-05 01:09 UTC | 2025-12-05 01:09 UTC | 0 min | resolved |
| [Claude.ai is unavailable](https://rewindex.com/company/anthropic/incidents/49cmvxrrk228.md) | critical | 2025-12-05 09:02 UTC | 2025-12-05 09:33 UTC | 31 min | resolved |
| [Claude.ai is unavailable](https://rewindex.com/company/anthropic/incidents/h183k7hqb9lk.md) | major | 2025-12-05 10:47 UTC | 2025-12-05 11:27 UTC | 40 min | resolved |
| [iOS Subscription Access Issues](https://rewindex.com/company/anthropic/incidents/6rrnsb1y0kbn.md) | minor | 2025-12-08 01:00 UTC | 2025-12-12 00:04 UTC | 4 d | resolved |
| [Research on claude.ai down](https://rewindex.com/company/anthropic/incidents/fmck9hh84rgf.md) | minor | 2025-12-10 19:44 UTC | 2025-12-10 20:21 UTC | 37 min | resolved |
| [Unable to start chats on claude.ai](https://rewindex.com/company/anthropic/incidents/h140lstlzbw7.md) | major | 2025-12-12 08:00 UTC | 2025-12-12 08:00 UTC | 0 min | resolved |
| [Elevated errors on documentation site in Europe](https://rewindex.com/company/anthropic/incidents/vdvhnlkdx045.md) | none | 2025-12-12 17:10 UTC | 2025-12-12 18:59 UTC | 1.8 h | resolved |
| [Elevated errors across many models](https://rewindex.com/company/anthropic/incidents/9g6qpr72ttbr.md) | critical | 2025-12-14 21:31 UTC | 2025-12-14 22:51 UTC | 1.3 h | resolved |
| [Unable to view shared chats on claude.ai](https://rewindex.com/company/anthropic/incidents/9x1dk1mmlkd3.md) | minor | 2025-12-15 18:39 UTC | 2025-12-15 19:29 UTC | 50 min | resolved |
| [Cannot create new conversations on Claude.ai](https://rewindex.com/company/anthropic/incidents/2f7kwfs03p6v.md) | critical | 2025-12-16 16:23 UTC | 2025-12-16 16:43 UTC | 20 min | resolved |
| [New chats defaulting to Claude Opus](https://rewindex.com/company/anthropic/incidents/z9kwvvpg0hy0.md) | major | 2025-12-16 19:30 UTC | 2025-12-16 20:52 UTC | 1.4 h | resolved |
| [Elevated error rates on Sonnet 4](https://rewindex.com/company/anthropic/incidents/4pw74ts6z930.md) | minor | 2025-12-17 10:45 UTC | 2025-12-17 11:20 UTC | 35 min | resolved |
| [Elevated error rates on Sonnet 4.5](https://rewindex.com/company/anthropic/incidents/8d87293jq0mk.md) | minor | 2025-12-19 04:34 UTC | 2025-12-19 13:52 UTC | 9.3 h | resolved |
| [Claude Code on Windows rendering improperly](https://rewindex.com/company/anthropic/incidents/8rwc17y9kmqz.md) | minor | 2025-12-19 20:30 UTC | 2025-12-19 22:14 UTC | 1.7 h | resolved |
| [Research unavailable for some teams orgs](https://rewindex.com/company/anthropic/incidents/3gvzshr7mqtr.md) | minor | 2025-12-20 00:51 UTC | 2025-12-20 01:35 UTC | 44 min | resolved |
| [Elevated error rates on Opus 4.5](https://rewindex.com/company/anthropic/incidents/d2w4wfsd7fq6.md) | minor | 2025-12-21 13:16 UTC | 2025-12-21 14:34 UTC | 1.3 h | resolved |
| [Elevated error rates on Opus 4.5](https://rewindex.com/company/anthropic/incidents/8f0x9qxn6bvf.md) | minor | 2025-12-22 07:18 UTC | 2025-12-22 09:32 UTC | 2.2 h | resolved |
| [Elevated error rates on Opus 4.5](https://rewindex.com/company/anthropic/incidents/f9zwsv7f87wl.md) | minor | 2025-12-23 09:55 UTC | 2025-12-23 10:51 UTC | 56 min | resolved |

## Cite this

Anthropic posted 21 status incidents in December 2025 (8 major or critical); 0 price changes and 0 notable page changes observed.

- Canonical URL: https://rewindex.com/company/anthropic/2025/12
- Citation: Anthropic, “Anthropic in December 2025” (2025-12-01 00:00 UTC). Archived by Rewindex: https://rewindex.com/company/anthropic/2025/12 (CC BY 4.0).
- Markdown link: `[Anthropic: Anthropic in December 2025 (2025-12-01)](https://rewindex.com/company/anthropic/2025/12)`


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Canonical: https://rewindex.com/company/anthropic/2025/12 · Markdown: https://rewindex.com/company/anthropic/2025/12.md · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-11-04T15:55:36.286Z