Claude Sonnet 5 Is Live — Anthropic's New Workhorse for Coding and Agents

July 1, 2026

Claude Sonnet 5 is in the model picker today. It's Anthropic's newest Sonnet — near-Opus intelligence for coding and agentic workflows, a 1M-token context window, always-on adaptive thinking, and 128K max output. It sits in the Premium token band (same as Sonnet 4.6), and the Auto router can pick it in the Workhorse tier when you're not pinned to a specific model.

What you can do

• Pick Claude Sonnet 5 — Reasoning from the model selector on any plan.
• Long-horizon coding and agent work — multi-step refactors, tool-heavy research loops, and projects where Sonnet 4.6 was good but you want the latest Anthropic workhorse.
• 1M context, adaptive thinking — the model decides how deeply to reason per turn; effort defaults to medium in the catalog.
• Swarm-eligible — multi-agent plans can assign Sonnet 5 to worker steps when EU Data Residency is off.
• Auto-routable — tagged Workhorse tier with a higher quality score than Sonnet 4.6, so Auto may prefer it on complex turns.

Where this shows up

• You're running a long agent loop with many tool calls and want Anthropic's newest Sonnet without jumping to Opus pricing.
• You have a large codebase or document corpus that fits in one pass and need strong coding quality at Premium-band cost.
• Sonnet 4.6 was your default Anthropic pick — Sonnet 5 is the direct upgrade in the same band.

Try it

• "Refactor this module for async I/O, keep the public API stable, and explain every breaking-risk change."
• "Plan a three-step research swarm: market scan, competitor pricing, then a one-page recommendation."
• "Hold this entire repo context and find the three architectural decisions that will hurt us at 10× scale."

Heads up

Update, August 15, 2026: the two residency notes below no longer apply. AWS has since published an EU inference profile for Sonnet 5, so the model is available under EU Data Residency and geofences to eu-west-2. See Claude Sonnet 5 Works With EU Data Residency.

• Premium band — 6× tokens. Same band as Sonnet 4.6; billed at the Premium multiplier on your plan quota.
• Global Bedrock routing only. AWS publishes Sonnet 5 with a Global inference profile (global.anthropic.claude-sonnet-5), not an EU geo profile. Requests may route outside the EU for throughput.
• Hidden when EU Data Residency is on. If you've enabled EU Data Residency (Digital Twin maker, or via chat), Sonnet 5 is excluded from the picker, Auto, and Swarm — same rule as other Global-only models. Users in Europe who have not turned that on can still select it.