Anthropic releases Claude Haiku 5.5, claims ~75% lower running cost than Haiku 4.5

Anthropic released Claude Haiku 5.5 on October 7, 2026, and claims the model costs around 75% less to run than Claude Haiku 4.5, which it replaces. Anthropic describes it as "the cheapest, fastest, and most capable small model we've ever released."

What Anthropic announced

Haiku 5.5 moves the small-model tier from version 4.5 to 5.5. According to 9to5Mac, the previous Haiku upgrade came about a year ago. It is the third Claude 5.5 model in roughly a month, following Opus 5.5 and Sonnet 5.5.

Anthropic positions Haiku 5.5 for "high-volume, cost-sensitive tasks." The company lists these target workloads:

• Summaries, compactions, database queries and classification requests
• Subagent work alongside Opus 5.5 and Sonnet 5.5 on coding tasks
• Speed-sensitive uses such as live customer support and browser use

Anthropic says Haiku 5.5 is its fastest model to date. No latency or throughput figures were included in the coverage reviewed.

Pricing and platform changes

The launch includes two other changes, according to Anthropic:

• Sonnet 5.5 cache reads are halved in price. Anthropic says this makes Sonnet 5.5 run around 20% cheaper on most agentic work.
• A new monthly API credit for Claude Max and Team subscribers, intended for building agents and applications on the Claude Platform.

The ~75% cost reduction, the ~20% agentic savings and the "most capable small model" description are Anthropic's own claims. They have not been independently verified.

Not yet disclosed

The coverage we reviewed does not include:

• Per-million-token input and output pricing: not yet disclosed
• Context window size: not yet disclosed
• Benchmark scores: not yet disclosed
• Parameter count and training data cutoff: not yet disclosed

Anthropic's website compares Haiku 5.5 to OpenAI's GPT-5.5 Luna, another low-cost model. We have not confirmed the figures behind that comparison.

Per 9to5Mac, Anthropic's lineup now runs from Haiku (smallest, cheapest) through Sonnet and Opus to a higher tier called Fable/Mythos, which is more capable and more expensive.

What this means

A 75% cost reduction, if it holds in production, matters most for teams running high-volume pipelines. Classification, summarization and compaction are workloads where per-token cost often decides whether a feature ships.

The subagent framing is also telling. Anthropic is pitching Haiku 5.5 as the cheap executor in multi-model coding setups, with Opus 5.5 or Sonnet 5.5 planning and Haiku handling the repetitive steps. The halved Sonnet 5.5 cache read price points the same way. Agentic workloads re-read large contexts repeatedly, so cache pricing dominates their bills.

The naming of GPT-5.5 Luna as the comparison point shows low-cost models are now a direct competitive front. Until Anthropic publishes token prices and benchmark results, the real savings and the capability gap against Luna can't be assessed. Developers should test on their own workloads and wait for the full pricing table before migrating from Haiku 4.5.