`ANTHROPIC_BEDROCK_REGION_PREFIX`

A Claude Code environment variable, read out of the shipped bundle. It has been in the build since v2.1.224, including the newest one read.

What it is

Cross-region inference profile prefix (us, eu, apac, jp, au, or global) Claude Code tries first instead of the one derived from the AWS region. Ignored in AWS GovCloud regions. Requires Claude Code v2.1.224 or later. See [Amazon Bedrock](/docs/en/amazon-bedrock#cross-region-inference-profile-prefixes)

Anthropic's own wording. Read off Environment variables, captured 2026-08-28.

Presence across releases

Releases	Reading	Declared type	Default
2.1.245 – 2.1.250 5 releases	never mined	—	—
2.1.224 – 2.1.243 19 releases	in the build	enum	—

A row reading never mined is a release with no archived bundle behind it. Nothing was read out of it, so nothing here says whether the name was in it. A declared type or a default is only ever what that release's own bundle stated.

Changelog entries naming it

v2.1.224ANTHROPIC_BEDROCK_REGION_PREFIX pins the Bedrock inference-profile region
Set ANTHROPIC_BEDROCK_REGION_PREFIX to pick which regional inference profile your Bedrock models resolve to.

named in this entry
v2.1.224Two warnings when a Bedrock region prefix cannot be confirmed
Bedrock now warns when it can't confirm a region prefix, or when models resolve elsewhere.

named in this entry

Documentation pages

Environment variables reference table Claude Code CLI
Claude Code on Amazon Bedrock mentions it Claude Code CLI
Claude Code changelog mentions it Claude Code CLI

A reference table page is one whose own table defines this name, and it is where the description above came from. A page that mentions it carries the name somewhere in its text and may say nothing about it at all. Every page carrying it.

Names beside it

Every environment variable in the inventory starting anthropic_bedrock, up to twelve of them.

ANTHROPIC_BEDROCK_BASE_URLOverride the Amazon Bedrock endpoint URL. Use for custom Amazon Bedrock endpoints or when routing through an [LLM gateway](/docs/en/llm-gateway). See [Amazon Bedrock](/docs/en/amazon-bedrock) 2.1.138 ANTHROPIC_BEDROCK_MANTLE_BASE_URLOverride the Amazon Bedrock Mantle endpoint URL. See [Mantle endpoint](/docs/en/amazon-bedrock#use-the-mantle-endpoint) 2.1.138 ANTHROPIC_BEDROCK_SERVICE_TIERAmazon Bedrock [service tier](https://docs.aws.amazon.com/bedrock/latest/userguide/service-tiers-inference.html) (default, flex, or priority). Sent as the X-Amzn-Bedrock-Service-Tier header. See [Amazon Bedrock](/docs/en/amazon-bedrock#service-tiers) 2.1.138

Read out of the published npm bundle release by release, and out of Anthropic's own documentation as this site captured it. Nothing on this page is a description anybody here wrote about what the environment variable does. All environment variables.