New modelReleased 22 September 2026 · 3 min read
The top model got cheaper, and easier to read.
Claude Opus 5.5 is the first model in Anthropic’s 5.5 family. Anthropic says it performs at the level of Claude Fable 5.1 on most work and costs 40% less to run than Opus 5 on typical workloads. Its developer documentation now tells most teams to start with Opus 5.5.
At a glance
- Model
- Claude Opus 5.5
- Price per M tokens
- $4 in · $20 out
- Context
- 1M in · 128k out
- vs Opus 5
- ~40% cheaper
- Best for
- Judgment, long documents
01 · What changed
What Anthropic shipped.
For a company, two changes matter more than the benchmarks. Its writing is clearer and puts the important information first, so its work is easier to check. And Anthropic raised the five-hour usage limits on Pro, Max, Team and seat-based Enterprise plans, so fewer people stop halfway through a long task.
Price
$4 / $20
Per million input / output tokens, 20% below Opus 5. Cache reads $0.20, 60% below.
Capacity
1M tokens
Context window by default, up to 128k output, and output more than 30% faster than Opus 5.
Usage limits
Higher
Five-hour limits raised on Pro, Max, Team and seat-based Enterprise plans, plus a saved rate limit reset.
02 · Where it sits
Which Claude for which job.
03 · What it means
What it means for your seat.
The work where firms get the most from Claude is long, careful reading: a credit agreement, a quarter of portfolio reporting, a stack of diligence material. That is Opus work, and it just got cheaper and easier to review.
Leadership
The most capable everyday model now costs less than the one it replaces. If seat cost or API spend held back a wider rollout, the arithmetic has moved.
Your teams
Clearer writing matters more than it sounds. The slowest part of using AI on real work is checking the output, and a draft that leads with its conclusion and cites its source is faster to check.
Risk and compliance
Anthropic reports Opus 5.5 is more resistant than Opus 5 to prompt injection and much less likely to take hard-to-reverse actions. That matters once Claude reads documents and email from outside the firm. A person still reviews what goes out.
IT and engineering
Through the API, thinking cannot be disabled on Opus 5.5: requests that try return a 400 error, and depth is set with the effort parameter instead. Forced tool use also returns a 400. Read the migration guide before switching.
04 · This week
What to do this week.
0 of 3 done
Sources
Facts and dates are Anthropic’s own. What it means and what to do are our view, from the firms we work with. Drafted with Claude from these sources, reviewed by Fatjon (Tony) Kalemaj and published 13 October 2026.
The short answers.
How much does Claude Opus 5.5 cost?
$4 per million input tokens and $20 per million output tokens on the Claude API, with cache reads at $0.20 per million. Anthropic says that works out to about 40% less than Claude Opus 5 on typical workloads.
Is Claude Opus 5.5 better than Claude Fable 5.1?
Anthropic says Opus 5.5 performs at the level of Fable 5.1 on most work, at a lower price. Its documentation recommends Fable 5.1 for the most demanding reasoning and long-horizon agentic work, or when Opus 5.5 at higher effort still falls short on your own tests.
Did Claude usage limits go up with Opus 5.5?
Yes. With the launch on 22 September 2026, Anthropic increased five-hour usage limits on Pro, Max, Team and seat-based Enterprise plans, and gave subscribers a rate limit reset they can save and use later.
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