Migrate to Amazon S3 account regional namespaces

This article explains how to migrate existing Amazon S3 buckets from the global namespace to the new account regional namespace feature introduced in March 2026.

• Account regional namespaces scope bucket names to individual AWS accounts and regions
• Deleted names remain reserved for your account, unlike global namespace buckets
• Migration uses S3 Replication to sync data while workloads remain on old buckets
• Five-step process: create new bucket, set up replication, update references, transition, retire old bucket
• Use AWS Organizations SCPs to enforce account regional namespaces for new buckets
• Phased enforcement recommended: sandbox first, then dev/staging, finally production
• Only incremental cost is temporary S3 storage and replication charges during migration
• Existing global namespace buckets continue working; migration is optional but recommended

Organizations should start with sandbox accounts and enforce account regional namespaces progressively as environments are migrated.