Sonnet 5 Stays at $2/$10 Per Million Tokens: Anthropic Cancels the September Price Increase

Anthropic locked Sonnet 5 at $2/$10 per million tokens permanently — the planned 50% September 1 price increase is canceled.

In an August 10 announcement, Anthropic made Claude Sonnet 5's introductory pricing permanent. The $2 input / $10 output per million token rate that launched in June will not step up to $3/$15 on September 1 — that planned increase is officially off.

One nuance remains: Sonnet 5's tokenizer produces ~30% more tokens from the same text as Sonnet 4.6, so effective cost comparisons across model generations still require accounting for that. But for anyone already running Sonnet 5 workloads, the rate is now stable indefinitely.

Why it matters: Any agent pipeline budgeted around a September 1 50% increase can drop that assumption. Lock in your model-tier routing now — $2/$10 is the permanent Sonnet 5 rate.

Sources: @claudeai announcement · Techmeme coverage · Analysis — explainx.ai