**Recent price cuts and efficiency gains amid intensifying competition are shaping sentiment around Anthropic's 2026 frontier output token pricing.** In late September 2026, Anthropic released Claude Opus 5.5 at $4 input and $20 output per million tokens—a 20% reduction from Opus 5—while claiming 40% lower effective costs on typical workloads due to improved efficiency, over 30% faster output, and sharply reduced cache-read rates at $0.20 per million. This positions the model near Fable 5.1 performance levels for agentic coding and knowledge work at lower cost. OpenAI responded with matching cuts on GPT-6 variants, accelerating a broader price war that has driven the frontier token price index down sharply from 2023 baselines. Traders are watching for further repricing in the expected Sonnet 5.5 and Haiku 5.5 releases, alongside any shifts in caching discounts, batch pricing, or regulatory factors that could influence list or effective rates through year-end.