The short version
In July 2026 Anthropic's pricing page described Claude Sonnet 5's $2 per million input / $10 per million output tokens as introductory pricing through August 31, 2026, with $3 / $15 per MTok from September 1. That is a 50% increase on both sides. We published this guide on the strength of that announcement.
The increase has not taken effect. Anthropic's pricing page listed Sonnet 5 at $2 / $10 on September 21 and again on 2026-11-02, with no introductory label. (Source: Anthropic's pricing page, verified 2026-11-02.) Our pages kept warning about the increase after September 1. We have corrected them, and our refresh now flags any scheduled price change whose date passes without the rate card moving.
What to budget
Budget at the live rate. A workload of 50M input + 10M output tokens/month on Sonnet 5 costs $200/month at $2 / $10. The announced $3 / $15 would have made it $300.
- Batch what can wait. The Batch API halves both sides, to $1 / $5 per MTok.
- Cache what repeats. Cache reads are listed at $0.20 per MTok, 0.1× the input rate.
- Keep a margin. We have not found a statement from Anthropic on whether the increase was dropped or only delayed. If it lands, the same workload costs 50% more. We re-verify the rate card every week and will update this page when it changes.
Where Sonnet 5 sits in the table
Of the 40 active models in our verified table, 14 are cheaper than Sonnet 5 on combined input+output rate ($12 per MTok-pair). The full ranking is on the pricing table.
Remember the tokenizer footnote: Sonnet 5 tokenizes ~30% heavier than pre-4.7 Claude models, so cross-family comparisons need real-payload benchmarks, not just rate cards.