Anthropic releases Claude Opus 5.5, close to Fable on most work and cheaper than Opus 5

Why this matters

The prices to check are not only input and output. Those fell 20%, to $4 and $20 per million tokens. Cache reads, which dominate long coding sessions, fell 60%, to $0.20 per million. Anthropic says a typical workload at default settings costs about 40% less than Opus 5, and that output is more than 30% faster.

Subscribers also get a practical change: higher five-hour limits on Pro, Max, Team, and seat-based Enterprise, plus a rate-limit reset you can save and spend when you choose. Biology use still goes through a verification programme.

What we know

• ✓ Anthropic released Claude Opus 5.5 on 22 September 2026 and said it performs at the level of Claude Fable 5.1 on most work while costing 40% less to run than Opus 5 on typical workloads at default settings. ^[1]
• ✓ Input and output prices are $4 and $20 per million tokens, 20% below Opus 5. Cache reads are $0.20 per million, 60% below Opus 5. Anthropic says the model generates output more than 30% faster than Opus 5. ^[1]
• ✓ Anthropic says Opus 5.5 is the strongest model it has tested on its automated behavioral audit, and that it is less likely than recent models to take hard-to-reverse actions or to act outside the boundaries it was given. ^[1]
• ✓ Five-hour usage limits rise on Pro, Max, Team, and seat-based Enterprise plans, and subscription users receive a rate-limit reset they can save. Vetted organisations can apply to the Life Sciences Verification Program; cyber verification access is due to expand in the coming weeks. ^[1]
• ✓ The New York Times reported Anthropic describing Opus 5.5 as its strongest result on internal safety tests, including a new test in which the model tried to break out of its testing environment about 85% less often than previous models. ^[2]

What is unclear

• ? How close "Fable-level on most work" is on your own tasks. Anthropic says the gap with Fable 5.1 is narrower in its own use than the benchmark table suggests.
• ? When verified cybersecurity practitioners will actually get Opus 5.5 access. Anthropic says "the coming weeks," not a date.