claude-sonnet-5-5 retirement date and replacement

Name: claude-sonnet-5-5 retires (Claude API)
Start: 2027-09-28
End: 2027-09-28

Claude API · Model · not sooner than Sep 28, 2027Unverified

Dates

Checked Oct 5, 2026 on Anthropic's page

Not sooner than	Sep 28, 2027 (not sooner than)The earliest date the vendor gives for a current model; the real date is announced later.
Replacement	None named
Model page	models.fru.dev/models/claude-sonnet-5-5
Notice	Tentative: not sooner than this date
Source	platform.claude.com/docs/en/about-claude/model-deprecations

Announced
Oct 5today
2027-09-28 (not sooner than). Tentative: not sooner than this date

Date	Change	Source
Oct 5today	Announced2027-09-28 (not sooner than)UnverifiedTentative: not sooner than this dateSource	Source