On October 29, 2026, Anthropic will remove Claude Haiku 4.5 from the model selector in chat, Claude Cowork and Claude Design. The change affects the Free, Pro and Max plans, including the Claude Desktop and Claude Mobile apps. Haiku 5.5, released October 7, takes its place. Anthropic announced the change on October 15 in a help center article.
If Haiku 4.5 is your selected model on that date, Claude will switch you to Haiku 5.5 automatically. Your Haiku 4.5 chats stay in your account, but if you pick one back up after October 29, Haiku 5.5 will answer. Think of a freelancer who hands Haiku the quick jobs: sorting email, summarizing a document, rewording a client reply. In under two weeks, a different model will be answering in those same chats.
Timeline and affected plans
Until October 29, you can still pick Haiku 4.5 under “More models.” Starting that day, it no longer appears in the selector. Anthropic launched the model on October 15, 2025, so it will have spent a little over a year in the Free, Pro and Max selector.
The diagram follows the list Anthropic published. A small team on the Team plan keeps Haiku 4.5, while a solo consultant on Pro will only find it in Claude Code. Our comparison of the Pro, Max and Team plans explains how they differ.
Your Haiku 4.5 chats stay in your account
Anthropic says nothing is deleted: your Haiku 4.5 chats stay in your account. You can also switch models at any point in a chat. The new model takes over starting with Claude’s next response.
To switch, click the model name next to the send button, then pick another one or click “More models.” The help center also explains how to change the model, effort and thinking settings. If you want a copy of your chats, you can export your Claude data at any time.
The chats most affected are the ones you reopen often and where you’ve dialed in a tone, a reply length or a table format. They’ll still be there, but a different model will reply.
Haiku 5.5 steps in
Anthropic calls Claude Haiku 5.5 “the cheapest, fastest, and most capable small model we’ve ever released.” It’s the first Haiku with an adjustable effort setting, which controls how much thinking it puts into a request. According to the help center, its context window is 1 million tokens in chat on paid plans and 500,000 in Cowork, compared with 200,000 for Haiku 4.5 in both. Its model page puts its reliable knowledge cutoff at June 2026, versus February 2025 for the older model.
The API price gap is wide: Haiku 5.5 starts at $0.10 per million input tokens, versus $1 for Haiku 4.5 (about €0.09 versus €0.89 at the European Central Bank rate of October 16, 2026). The $0.10 rate applies to requests of up to 100,000 tokens. Once the new tokenizer is factored in, Anthropic says Haiku 5.5 costs about 75% less to run on average.
Our article on the launch of Claude Haiku 5.5 breaks down the pricing and its conditions. For help choosing between Haiku, Sonnet, Opus and Fable for a given task, see our guide to Claude models. The performance figures published for Haiku 5.5 come from Anthropic and its customers, so test it on your own requests before you rely on it for recurring work.
Team, Enterprise, Claude Code and the API keep Haiku 4.5
The change doesn’t affect the API, Claude Code or the Team and Enterprise plans. Say an outside developer wired an automation to Haiku 4.5 through the API to sort quote requests or summarize form submissions. It will keep running on October 29.
It won’t run forever, though. Haiku 4.5’s model page already labels it “Legacy,” which Anthropic defines as a model that no longer receives updates and may be deprecated. Anthropic’s model deprecations page still lists it as “Active,” with a tentative retirement date of “not sooner than October 15, 2026,” a date that has already passed.
As of October 17, Anthropic hasn’t announced a firm retirement date for the API. It says it notifies affected customers by email at least 60 days before it retires a publicly released model.
To find out which API keys still call Haiku 4.5, export your usage by key and by model from the Usage page of the Claude Console. Before you move an automation to Haiku 5.5, rerun the numbers: according to Anthropic’s documentation, the same text produces about 30% more tokens on the new model. Some settings the old model accepted, such as a manual thinking budget or a non-default temperature, return an error on Haiku 5.5.
Six checks before October 29
- Open a chat and look at the model name next to the send button. If it says Haiku 4.5, Claude will switch your account to Haiku 5.5 on October 29.
- Make a list of the Haiku 4.5 chats you reopen every week, plus any Cowork or Design tasks you run on that model.
- Run one of your typical requests on Haiku 5.5 now, then compare the tone, length and format with what you usually get.
- If you’re less happy with the result, adjust your prompt or try Sonnet before the switch.
- Export your data if you want to keep a copy outside Claude.
- Ask whoever built your API automations which model each one calls, and plan their move to Haiku 5.5 before a retirement date is announced.
Questions Anthropic’s page leaves open
The help article doesn’t say whether you’ll hit the Pro and Max usage limits faster or slower on Haiku 5.5 than on its predecessor. If you regularly come close to the cap, keep an eye on your usage for the first few days. Our article on hitting the limit on Claude Pro explains how those caps work. The page also says nothing about Claude Projects and only covers chats, Cowork and Design.
OpenAI is clearing out older models too. GPT-5.5 left ChatGPT on October 14, as our article on the end of GPTs and GPT-5.5 explains.
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