Introducing account regional namespaces for Amazon S3 general purpose buckets | Amazon Web Services

Amazon S3 now lets customers create general purpose buckets in an account regional namespace, making bucket names predictable and reusable across AWS Regions. Names combine a customer-selected prefix with an account-, Region-, and namespace-specific suffix, preventing other accounts from claiming them. The feature preserves existing general purpose bucket capabilities while improving governance and automation.

Account Regional Bucket Namespaces

• Bucket names use a format such as mybucket-123456789012-us-east-1-an.
• The suffix identifies the AWS account and Region, ensuring that other accounts cannot create buckets using it.
• The combined prefix and suffix must be between 3 and 63 characters.
• Buckets support the same features as general purpose buckets in the global namespace.

Governance and Policy Controls

• IAM policies and AWS Organizations service control policies can enforce namespace usage.
• The new s3:x-amz-bucket-namespace condition key allows organizations to require account regional bucket creation.

Creating Buckets

• In the S3 console, select Account regional namespace when creating a bucket.
• AWS CLI requests use the --bucket-namespace account-regional option.
• SDKs can pass BucketNamespace: "account-regional" to the CreateBucket API.
• Applications can use STS to retrieve the account ID and the SDK’s Region to construct compliant names.

Infrastructure as Code

• CloudFormation templates can use AWS::AccountId and AWS::Region to construct bucket names.
• The BucketNamespace: "account-regional" property enables the feature.
• BucketNamePrefix can be used when only the customer-defined prefix should appear in the template; AWS adds the account regional suffix automatically.

Limitations and Availability

• Existing global-namespace buckets cannot be renamed into the account regional namespace; new buckets must be created.
• The feature applies only to S3 general purpose buckets.
• S3 table and vector buckets use account-level namespaces, while directory buckets use zonal namespaces.
• It is available in 37 AWS Regions, including AWS China and GovCloud Regions, with no additional cost.

Organizations can adopt account regional namespaces to simplify bucket provisioning, prevent naming conflicts, and enforce consistent naming through IAM, Organizations policies, and infrastructure-as-code tools.