# Anthropic Claude Instant 1.1 — deprecation status

> Yes — Claude Instant 1.1 is retired. Anthropic deprecated it on September 4, 2024 and shut it down on November 6, 2024; API requests to it now fail. The recommended replacement is Claude Haiku 4.5.

The middle Instant release, and the one that widened the context window enough to make document summarisation practical at Instant pricing. Retired alongside the whole Claude 1 generation in November 2024.

## Facts

| Field | Value |
| --- | --- |
| Provider | Anthropic |
| Model id | `claude-instant-1.1` |
| Status | Retired |
| Deprecated | September 4, 2024 |
| Shutdown | November 6, 2024 (631 days ago) |
| Last verified | July 30, 2026 |

## Replacement

- **Claude Haiku 4.5** (`claude-haiku-4-5-20251001`) · recommended — https://modeldeprecations.dev/anthropic/claude-haiku-4-5-20251001
  - Two generations and a whole API separate these. Claude 1 predates the Messages API, so a migration means moving off /v1/complete and its "\n\nHuman:"/"\n\nAssistant:" prompt format entirely.
  - Parameters it accepts: https://modelparams.dev/models/anthropic/claude-haiku-4-5-20251001

```diff
- "model": "claude-instant-1.1"
+ "model": "claude-haiku-4-5-20251001"
```

## FAQ

### When did Anthropic Claude Instant 1.1 shut down?

Anthropic Claude Instant 1.1 shut down on November 6, 2024. API requests to it fail from that date onward.

### What replaces Anthropic Claude Instant 1.1?

Anthropic recommends Claude Haiku 4.5 (`claude-haiku-4-5-20251001`) as the replacement for Anthropic Claude Instant 1.1. Two generations and a whole API separate these. Claude 1 predates the Messages API, so a migration means moving off /v1/complete and its "\n\nHuman:"/"\n\nAssistant:" prompt format entirely.

### Is Anthropic Claude Instant 1.1 still available?

No. Anthropic Claude Instant 1.1 is retired and no longer served — it was shut down on November 6, 2024. Calls to it return an error.

### How do I migrate from Anthropic Claude Instant 1.1 to claude-haiku-4-5-20251001?

Swap the model id in your API call: replace "claude-instant-1.1" with "claude-haiku-4-5-20251001". Two generations and a whole API separate these. Claude 1 predates the Messages API, so a migration means moving off /v1/complete and its "\n\nHuman:"/"\n\nAssistant:" prompt format entirely.

## Sources

- [Anthropic model deprecations](https://platform.claude.com/docs/en/about-claude/model-deprecations) — accessed 2026-07-30

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Canonical page: https://modeldeprecations.dev/anthropic/claude-instant-1.1
JSON: https://modeldeprecations.dev/api/v1/models/anthropic/claude-instant-1.1.json