GPT-5.5, GPT-5.4 and Codex reach Amazon Bedrock, ending Azure exclusivity

The arrival of OpenAI's flagship models on Amazon Bedrock is a structural shift: for years OpenAI's API was effectively Azure-exclusive through its Microsoft partnership. Putting GPT-5.5, GPT-5.4 and Codex on Bedrock means AWS-native enterprises can call OpenAI models under the same IAM roles, procurement contracts and billing they already use — removing a major reason to maintain separate Azure infrastructure.

The move slots into AWS's strategy of turning Bedrock into a neutral multi-model marketplace, now hosting OpenAI, Anthropic Claude and open-weight models side by side. A Reddit thread on r/LocalLLM ("OpenAI on Bedrock — Azure exclusivity is dead") documented developers running GPT-5.5 on AWS for the first time.

But the rollout was messy. On r/aws, users asked "Is GPT 5.5 available on AWS? I keep reading it is" amid reports that access was gated behind a "limited preview" despite GA messaging, with console support delayed and confusion over what's actually callable. That friction tempers the significance for teams hoping to migrate immediately.

Strategically, the end of Azure exclusivity weakens one of Microsoft's key differentiators and gives OpenAI broader distribution ahead of its IPO — more reachable enterprise customers strengthens the revenue story. It also escalates the cloud-neutrality arms race: with both OpenAI and Anthropic now on Bedrock, AWS can credibly claim the widest frontier-model selection. Readers should watch whether the preview restrictions lift to true GA, and how pricing on Bedrock compares to OpenAI's direct API and Azure.