AWS Secrets Manager vs Parameter Store: How to Choose the Right Tool

AWS offers two primary secrets and configuration storage services — Secrets Manager and Systems Manager Parameter Store — both backed by KMS encryption, but suited to different use cases. Secrets Manager is purpose-built for sensitive credentials that require automatic rotation, cross-region replication, and cross-account sharing, at a cost of around $0.40 per secret per month. Parameter Store is a general-purpose hierarchical config store with a free standard tier, making it better suited for application configuration, feature flags, and static secrets that rarely change. The core decision rule is straightforward: if a secret needs to rotate on a schedule, use Secrets Manager; otherwise, Parameter Store is the more cost-effective choice. Choosing the wrong service at the start of a project can lead to expensive rewrites or unnecessary costs, making the upfront decision critical.