Claude Sonnet 5.5 lands in Cowork, faster and cheaper than before

Your move: Same price, faster results if your plan uses it

Anthropic released Claude Sonnet 5.5 on September 28, 2026, the second model in its new Claude 5.5 family after Opus 5.5. It produces output more than 30% faster and costs up to 30% less per task, with pricing unchanged at $2 per million input tokens and $10 per million output tokens. Anthropic says it is especially strong at well scoped everyday tasks, bug fixes, and polished documents, slides, and spreadsheets, the kind of work Cowork hands off to Claude. Claude Desktop added support for it the day before, in version 2.9939.4.

Why it matters

If Cowork is running tasks for you in the background, this newer model should get routine work done faster and for less, without you changing anything. If your plan lets you pick a specific model, it is worth checking that your account is actually using Sonnet 5.5.

Source: Anthropic ↗

Published by Agent Log. The summary reports the linked source; “Why it matters” and the verdict are Agent Log's interpretation.

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