# Anthropic — Introducing Claude Sonnet 5.5

- Company: Anthropic (anthropic.com)
- Announced: 2026-09-28
- Category: model-update
- Coverage: 24 outlets
- Announcement: yes
- Group: models
- Source: https://www.anthropic.com/claude-sonnet-5-5
- Record: https://forck.live/items/14728-introducing-claude-sonnet-5-5
- Subject: Claude
- Models affected: Claude Sonnet 5.5, Claude Sonnet 5, Claude Opus 5.5, Claude Haiku 5.5
- Pricing: $2 per million input tokens, $10 per million output tokens, and $0.20 per million tokens for cache reads

Anthropic released Claude Sonnet 5.5, the second model in the Claude 5.5 family, as a faster and lower-cost complement to Claude Opus 5.5. It runs 30%+ faster than Sonnet 5 and costs up to 30% less per task, with the same per-token pricing but fewer tokens needed. Sonnet 5.5 scores 70.6% on Terminal-Bench 4.0, up from Sonnet 5's 10.3%, and is the first Sonnet model to launch with cyber safeguards and fallbacks.

## Evidence

Verbatim from https://www.anthropic.com/claude-sonnet-5-5:

> Sonnet 5.5 is priced the same as Sonnet 5 at $2 per million input tokens, $10 per million output tokens, and $0.20 per million tokens for cache reads, but it typically needs far fewer tokens to do the same work. In our testing, it costs up to 30% less per task than its predecessor.

## Around this story

Outlets this record can name and link:

- TechCrunch — Anthropic releases Sonnet 5.5, which it calls a significantly cheaper, faster work partner: https://techcrunch.com/2026/09/28/anthropic-releases-sonnet-5-5-which-it-calls-a-significantly-cheaper-faster-work-partner
- Gizmodo — Anthropic Releases Its Second New AI Model in Less Than a Week: https://gizmodo.com/anthropic-releases-its-second-new-ai-model-in-less-than-a-week-2000818514
- Digital Trends: https://digitaltrends.com/computing/anthropic-launches-claude-sonnet-5-5-with-30-faster-output-and-lower-per-task-costs
- Mashable — Anthropic releases Claude Sonnet 5.5: Details, pricing, how to try it: https://mashable.com/tech/anthropic-claude-sonnet-launch-cheaper-opus-model
- The New Stack — You picked Claude Sonnet 5.5 — but Anthropic may send your request to Sonnet 5: https://thenewstack.io/claude-sonnet-cyber-safeguards
- Moneycontrol — Anthropic launches Claude Sonnet 5.5 with 30% faster output, improved coding and cheaper task costs: https://moneycontrol.com/technology/anthropic-launches-claude-sonnet-5-5-with-30-faster-output-improved-coding-and-cheaper-task-costs-article-14040925.html
- 9to5Mac — Anthropic upgrades Claude with new Sonnet 5.5 model, details here: https://9to5mac.com/2026/09/28/anthropic-upgrades-claude-with-new-sonnet-5-5-model-details-here
- TestingCatalog — Anthropic launches Claude Sonnet 5.5 with faster output: https://testingcatalog.com/anthropic-launches-claude-sonnet-5-5-with-faster-output
- Unite — Anthropic Releases Claude Sonnet 5.5 at Unchanged Sonnet 5 Pricing: https://unite.ai/anthropic-releases-claude-sonnet-5-5-at-unchanged-sonnet-5-pricing
- Business Today — Anthropic introduces Claude Sonnet 5.5: Faster AI model promises lower costs: https://businesstoday.in/technology/news/story/anthropic-introduces-claude-sonnet-5-5-faster-ai-model-promises-lower-costs-558406-2026-09-29
- The Mac Observer: https://macobserver.com/news/claude-sonnet-5-5-faster-responses-token-prices
- Forkast: https://forkast.news/anthropics-sonnet-5-5-ships-safety-as-a-feature-a-federal-court-just-called-it-a-liability
- Decrypt — Anthropic's Claude Sonnet 5.5 Is Out, Beats Opus 5.5 at Coding for Half the Price: https://decrypt.co/379482/anthropic-claude-sonnet-5-5-release
- Finimize: https://finimize.com/content/anthropic-adds-claude-sonnet-55-ahead-of-an-ipo
- Ithinkdiff — Claude Sonnet 5.5 Launches Faster and 30% Cheaper per Task: https://ithinkdiff.com/claude-sonnet-5-5-launches-faster-lower-cost
- Thurrott — Anthropic Releases Claude Sonnet 5.5: https://thurrott.com/a-i/anthropic/342139/anthropic-releases-claude-sonnet-5-5
- Superpower Daily — Anthropic Releases Sonnet 5.5, Claiming Lower Task Costs Without Cutting Token Prices: https://superpowerdaily.com/posts/anthropic-releases-sonnet-5-5-claiming-lower-task-costs-without-cutting-token-prices
- Superpower Daily — GitHub Adds Claude Sonnet 5.5 to Copilot for Paid Users: https://superpowerdaily.com/posts/github-adds-claude-sonnet-5-5-to-copilot-for-paid-users
- Simon Willison's Weblog — Claude Sonnet 5.5: https://simonwillison.net/2026/Sep/28/claude-sonnet-5-5
- iClarified — Anthropic Launches Claude Sonnet 5.5 With Faster Output and Lower Per-Task Costs: https://iclarified.com/102465/anthropic-launches-claude-sonnet-55-with-faster-output-and-lower-per-task-costs
- WinBuzzer: https://winbuzzer.com/2026/09/28/anthropic-launches-claude-sonnet-5-5-ai-model-promises-cheaper-tasks-a002-xcxwbn
- Bitcoin Insider: https://bitcoininsider.org/article/308174/federal-court-calls-safety-feature-liability-new-sonnet-55-model
- Thenextweb — Anthropic releases Claude Sonnet 5.5 with the cyber limits it reserved for its best models: https://thenextweb.com/news/sonnet-5-5-cyber-distillation
- Searchenginejournal — Anthropic Publishes Prompting Guidance For Claude Opus 5.5: https://searchenginejournal.com/anthropic-claude-opus-5-5-prompting-guidance/591278

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