Anthropic · First-party API
claude-sonnet-4-6
ActiveAvailable until at least Feb 17, 2027
Anthropic lists claude-sonnet-4-6 as active and guarantees it until at least Feb 17, 2027. That is the earliest it could be retired, not a shutdown date; no retirement is announced. Source: platform.claude.com · checked Oct 23, 2026
What the provider published
API model name Current state Deprecated Tentative retirement date claude-sonnet-4-6 Active N/A Not sooner than February 17, 2027