Anthropic released Claude Sonnet 5.5 on September 28, 2026, and put it straight to work as the model behind Claude’s free chat tier on web, iOS and Android — no subscription needed. Anthropic says the model runs more than 30% faster and costs up to 30% less per task than the outgoing Sonnet 5, at the same API price developers already pay.
Same Login, New Model Underneath
Anthropic’s own pricing page lists Sonnet 5.5 as its newest Sonnet model, and shows every plan from Free upward as including “Sonnet” access — in practice, Anthropic swaps in the latest Sonnet for everyone already on that tier, which is what independent testers found within hours of the release: the free web app was already answering with Sonnet 5.5. Anthropic says the model is “now available on all platforms,” including the Claude apps, Claude Code, the Claude API, and cloud marketplaces on AWS, Google Cloud and Microsoft Azure. For developers, API pricing is unchanged from Sonnet 5: $2 per million input tokens, $10 per million output tokens, and $0.20 per million tokens for cache reads. A smaller Haiku 5.5 model is due to join the lineup “in the coming weeks,” Anthropic says, but isn’t out yet, and the company hasn’t published new message caps for the free tier.
For Support Teams Comparing AI Tools
- If staff already draft replies or summarise tickets on Claude’s free plan, the same login now runs a faster model at no added cost — worth a quick side-by-side against whatever tool is standard practice today.
- If a support script or integration calls Claude’s API directly, check whether it already points at
claude-sonnet-5-5; since per-token pricing hasn’t changed, a faster model doing the same job can lower the actual bill for the same volume of replies. - A general chat model like Claude answers one conversation at a time and doesn’t know a business’s own products, policies or order history — that’s a different job from a support AI trained on a business’s own knowledge base, like the AI Agents in 1CS, which hand off to a human with context when a case needs one.
For more on how AI pricing has moved this month, see Anthropic’s Opus 5.5 price cut and OpenAI’s GPT-6 Sol and Luna price cut.
