Anthropic API: Opus 5.5 launches, replaces Opus 5 as flagship
Opus 5.5 ("Daily driver for agentic coding and enterprise work") launched at $4/MTok input, $20/MTok output (cache read $0.20, write $5.00), replacing Opus 5 as the flagship model; Opus 5 moved to Legacy Models at its original $5/$25 pricing.
What changed
New flagship model Opus 5.5 ("Daily driver for agentic coding and enterprise work") launched at $4/MTok input, $20/MTok output, replacing Opus 5; Opus 5 moved to Legacy models at its original $5/$25 pricing.
Before and after
Sep 21, 2026 vs Sep 28, 2026New flagship model Opus 5.5 ("Daily driver for agentic coding and enterprise work") launched at $4/MTok input, $20/MTok output, replacing Opus 5; Opus 5 moved to Legacy models at its original $5/$25 pricing.
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More from Anthropic
Full history →- Q2 2026·packagingAnthropic API: Fast mode for Opus 4.8 + Managed Agents pricing added
- Week 25, 2026·packagingAnthropic API shifts Opus 4.8 focus to enterprise agentic coding
- Week 23, 2026·packagingAnthropic API launches Opus 4.8 with new fast mode for lightning speeds
- Week 20, 2026·improvedAnthropic API consolidates Microsoft 365 and Outlook integrations
- Week 17, 2026·packagingAnthropic API launches Managed Agents at $0.08 per session-hour of runtime
