Originally published on AI Tech Connect.
What changed on 22 September Anthropic released Claude Opus 5.5 on 22 September 2026. The headline for most teams is not the model, it is the price line underneath it. API list price is $4 per million input tokens and $20 per million output tokens. That is 20% below Opus 5, which listed at $5 and $25 — a rate that had held across every prior Opus release. Cache reads are $0.20 per million tokens, which Anthropic describes as 60% cheaper than Opus 5 cache reads. Fast mode is available in Claude Code and on the Claude Platform, runs up to 2.5 times faster, and is priced at $8 and $40 per million tokens. Anthropic's framing is roughly 40% less to run on typical token-billed workloads — an effective-cost claim, not a list-price claim. Availability is broad from day one: the Claude Platform,…
