Sonnet 4.6 1M context unavailable on Max 20x plan - only Opus 1M appears in /model

Found 3 possible duplicate issues:

1. https://github.com/anthropics/claude-code/issues/26557
2. https://github.com/anthropics/claude-code/issues/15057
3. https://github.com/anthropics/claude-code/issues/26428

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🤖 Generated with Claude Code

Worth noting: when 1M context does become available for Sonnet, be aware that crossing the 200K input threshold triggers premium pricing where all tokens (not just those over 200K) get billed at 2x input / 1.5x output rates.

For most coding tasks, staying under 200K with context optimization is cheaper and often produces better results since Claude has less noise to process.

Detailed breakdown of 1M context pricing mechanics: https://github.com/Sagargupta16/claude-cost-optimizer/blob/main/guides/01-understanding-costs.md#long-context-pricing-1m

I am confused because it is written everywhere that Sonnet 4.6 should have 1M available already and it still block at 200k for me. And it seems to create this issues where I can only use Opus and Haiku for now. I mainly do non coding task that requires context! (marketing etc)

But thanks a lot for your answer and all the ressources in your repo. I starred it and will defintely use it to learn how to optimize my usage+ + get better at token management ! @Sagargupta16

According to the 1M context GA announcement, Sonnet 4.6 should have 1M context available. If it is still blocking at 200K for you, that sounds like a bug rather than a pricing tier issue. The duplicate issues linked above (#26557, #15057) might have workarounds.

For non-coding tasks requiring large context, you could also try the API directly where 1M context is confirmed working for both Opus and Sonnet.

Likely the same underlying issue as #35269 — since ~2026-03-16 22:00 UTC, Max plan OAuth tokens return 400 {"type":"invalid_request_error","message":"Error"} for claude-sonnet-4-6 and claude-opus-4-6 specifically. Claude Code silently falls back to Haiku without notifying the user. The 1M context unavailability may be a symptom of Sonnet/Opus being blocked entirely rather than a separate context window issue.

We are facing the exact same problem.

Same issue here. I'm on MAX 5x with version cc v2.1.78.

I was under the impression sonnet would have 1M context at standard usage as well, but I still see it billed as extra usage, so I'm hesitant to use it for /opusplan, which already requires a workaround of:

grep 'opus' ~/.zshrc 
export ANTHROPIC_DEFAULT_OPUS_MODEL="claude-opus-4-6[1m]"

See here: https://github.com/anthropics/claude-code/issues/34454

sonnet[1m] showing extra usage as billable:

  Select model                                                                                                  
  Switch between Claude models. Applies to this session and future Claude Code sessions. For other/previous     
  model names, specify with --model.                                                                            
                                                                                                                
    1. Default (recommended)  Opus 4.6 with 1M context · Most capable for complex work                          
    2. Sonnet                 Sonnet 4.6 · Best for everyday tasks                                              
    3. Sonnet (1M context)    Sonnet 4.6 with 1M context · Billed as extra usage · $3/$15 per Mtok
    4. Haiku                  Haiku 4.5 · Fastest for quick answers
  ❯ 5. Opus Plan Mode ✔       Use Opus 4.6 in plan mode, Sonnet 4.6 otherwise

Additional repro — Max $200/mo plan (same as Max 20x)

Same issue here. Running Claude Code on macOS with Claude Max ($200/month) subscription.

The problem: /model sonnet works but drops to 200k context. /model sonnet[1m] returns:

Sonnet 4.6 with 1M context is not available for your account.
Learn more: https://code.claude.com/docs/en/model-config#extended-context-with-1m

Environment:

• Claude Code CLI: latest (regression likely introduced in v2.1.77 or v2.1.78)
• Claude Code macOS Desktop App: v1.1.7464 (build 2809b6, 2026-03-18)
• Plan: Claude Max ($200/month)
• OS: macOS Darwin 25.3.0 / zsh

Confirmed across all surfaces: The 200k cap is present in:

• Claude Code CLI (/context shows 14.6k / 200k)
• claude.ai/code
• Claude Code macOS desktop app (v1.1.7464)

/context screenshot showing 14.6k / 200k (7%) on claude-sonnet-4-6 — confirming only 200k window is active, not 1M. _(screenshot: see attached image)_

When it started: The regression appears to have occurred with either the v2.1.77 or v2.1.78 update — it was working prior to that.

Per the 1M context GA announcement, both Opus 4.6 and Sonnet 4.6 should be available with 1M context on Max plans. This is a regression — the feature should be available and is not functioning correctly.

The error message says "not available for your account" which is incorrect for Max subscribers. This appears to be a plan entitlement check bug rather than a feature being intentionally gated.

Yup still no luck on my end I tried injecting different models in settings.json and zhrc but it doesn't work. Because of having to use opus all the time I even reached out weekly limits for the first time :( does anyone has a solution?

Facing the same issue here on OSX and would be interested in a solution. I can get the model setup via the command /model sonnet[1m] but trying to run anything gives out an API error.

❯ /model sonnet[1m]
  ⎿  Set model to sonnet[1m] (claude-sonnet-4-6[1m]) · Billed as extra usage

❯ What is in this folder?
  ⎿  API Error: Rate limit reached

────────────────────────────────────────────────────────────────────────────────
❯
────────────────────────────────────────────────────────────────────────────────
  Sonnet 4.6 [1M] | ░░░░░▓ --%                                        0 tokens

Me paying 200 usd per month, and cannot use sonnet 1m, anthropic get some morality back please.

Max x20 plan — API error when using sonnet[1m]

Confirmed on Claude Max x20. Even after enabling extra usage with a spending limit, attempting to use sonnet[1m] (via "model": "sonnet[1m]" in settings.json or /model sonnet[1m]) results in an API error. Falls back or errors out entirely. The display bug in #34790 appears to be a separate symptom of the same underlying issue — on Max x20, 1M context for Sonnet is not accessible at all.

https://github.com/anthropics/claude-code/issues/38325

<img width="1016" height="340" alt="Image" src="https://github.com/user-attachments/assets/f04b1442-449d-44f7-8145-c0b83a47f19c" />

https://code.claude.com/docs/en/model-config#extended-context

DOES NOT MAKE ANY SENSE.

<img alt="Image" width="1016" height="340" src="https://private-user-images.githubusercontent.com/30603661/568534676-f04b1442-449d-44f7-8145-c0b83a47f19c.png?jwt=eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.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.PwJNZj-tWyhgN6fmFHMhhgPRg731qzVxcQRKepwkXts"> https://code.claude.com/docs/en/model-config#extended-context DOES NOT MAKE ANY SENSE.

I AM CONFUSION

Per the announcement:

Standard pricing now applies across the full 1M window for both models, with no long-context premium.

@thomassauve26 after re-reading the GA announcement, I see that only Claude Platform is mentioned to have both Opus and Sonnet 1M at standard pricing. Claude Code only gets 1M tokens for Opus apparently. It doesn't make sense to me.

Sonnet 4.6 1M context is not for Oauth accounts, only API. They are sneaky and want you to PAY PAY PAY

Makes no sense because Sonnet is a cheaper model, Opus is more, why not give sonnet[1m] before opus? We want SONNET 1m!!!!

Makes no sense because Sonnet is a cheaper model, Opus is more, why not give sonnet[1m] before opus? We want SONNET 1m!!!!

as @veryDead says, they want you to PAY PAY PAY. Every single decision they take as company is focused on how to consume as much as possible the user's rate limit

Yeah not including the 1m Sonnet in the Pro/Max plans is odd, I would basically use that exclusively post planning if enabled. It is odd as they seem to want to reduce usage and strain on there systems but include opus 1m but not sonnet 1m 🤷

actually there is a one trick that makes Sonnet[1m] and opusplan for 1m models work on Max plans.
opusplan with 1m window does the trick.

i have no idea that is a bug or not but it has been working for a month already.

i do not see bugs, i see features (c) vibe engineer.

Also affected. Claude Max plan, Claude Code v2.1.133 (latest as of May 7, 2026), macOS. /model shows Opus 4.6 (1M context) but no Sonnet 4.6 1M option. Sonnet 4.6 is listed without a 1M variant. Same steps to reproduce as above — /login, model toggling, and --model claude-sonnet-4-6 all confirmed. The 1M window does not appear to activate for Sonnet even when forced via CLI.

@elsahafy
1) i've enabled an extra usage;
2) added a few dollars;
3) i run Claude Code using following cmd: ANTHROPIC_DEFAULT_OPUS_MODEL="claude-opus-4-7[1m]" ANTHROPIC_DEFAULT_SONNET_MODEL="claude-sonnet-4-6[1m]" claude;
4) i can even use an opusplan with 1m context;
5) firstly, usage is counted against regular quota, only after against the extra usage.

Additional data point: Sonnet 4.6 [1M] not accessible on paid plan with extra usage confirmed enabled and used.

• Plan: paid (extra usage enabled - confirmed consumed in prior sessions)
• OS: Windows 10
• Behaviour: /model sonnet 4.6 [1M] accepts the string and reports success, but after a short delay the following error appears in red:

> API Error - There''s an issue with the selected model (sonnet 4.6[1m]). It may not exist or you may not have access to it. Run --model to pick a different model.

• The active session then falls back to standard claude-sonnet-4-6. The 1M variant is not visible in the model picker list, requiring the exact string to be typed manually.
• Support article at https://support.claude.com/en/articles/8606394 confirms this should be available on all paid plans with extra usage enabled.

This problem persists. How much time is needed to fix it in an IT company? Maybe people should start to ask partial refund of their plan because Anthropics is not providing what it is supposed to provide?
Don't you have in the USA class actions? ;)