When did Claude 4 shut down? June 15, 2026. But the shutdown didn't start there — and the impact is still unfolding. This timeline covers every date in the Claude 4 deprecation process, from the initial announcement through the post-shutdown aftermath. Whether you're just learning about this or still dealing with 410 errors, this is your complete roadmap.

The Complete Claude 4 Deprecation Timeline

Here's every key date in the Claude 4 shutdown process, with what happened (or has happened) and what you should do at each stage:

What Happened on June 15?

On June 15, 2026, Anthropic permanently removed the Claude 4 Opus and Claude 4 Sonnet model endpoints. Here's exactly what changed:

The Fix: If You're Still Seeing 410 Errors

If your application is still broken, here's the fastest fix — most developers complete this in under 5 minutes:

Option 1: Stay with Anthropic (Quickest Fix)

Update the model ID in your code. Same API key, same parameters, same code structure:

# Python
# Before (broken):
client.messages.create(model="claude-4-opus", ...)

# After (fixed):
client.messages.create(model="claude-opus-4-8", ...)  # 67% cheaper
# or:
client.messages.create(model="claude-sonnet-4-6", ...)  # 50% cheaper

# Node.js
// Before (broken):
{ model: "claude-4-sonnet" }

// After (fixed):
{ model: "claude-sonnet-4-6" }  // 50% cheaper

# curl
# Before (broken):
"model": "claude-4-opus"

# After (fixed):
"model": "claude-opus-4-8"  // 67% cheaper

Option 2: Switch Providers (Biggest Savings)

If you want to save 67-99% on API costs, switch to a cheaper provider. Here are the top alternatives:

10 Migration Guides — Step by Step

Choose your target provider and follow the step-by-step migration guide with code snippets, cost comparisons, and FAQ:

Migration Status: Where Are You Now?

Use this quick reference to find your current situation:

Key Numbers After the Shutdown

Frequently Asked Questions

Related Resources