When is claude-sonnet-4-5-20250929 retired?
Migration guide: What to Do Before Claude Sonnet 4.5 Shuts Down on November 30, 2026
deprecated
claude-sonnet-4-5-20250929 on Anthropic is scheduled to shut down on Nov 30, 2026.
Replacement: claude-sonnet-5-5
| Provider (API) | Anthropic |
|---|---|
| Model ID | claude-sonnet-4-5-20250929 |
| Deprecation announced | Sep 30, 2026 |
| Shutdown date | Nov 30, 2026 |
| Section on source page | Model status |
| Source | https://platform.claude.com/docs/en/about-claude/model-deprecations |
| Last checked | 2026-11-06T05:52:31+00:00 |
Last checked 2026-11-06 · Source · Markdown · JSON
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Migration
- Anthropic lists
claude-sonnet-5-5as the recommended replacement forclaude-sonnet-4-5-20250929(official source). - Read the provider's official notes on the source page before switching model IDs.
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