This is a practical comparison based on real production use, not vendor marketing.
Quick Comparison
| Feature | HashiCorp Vault | AWS Secrets Manager |
|---|---|---|
| Hosting | Self-hosted or HCP | AWS managed |
| Multi-cloud | Yes | AWS only |
| Dynamic secrets | Yes (DB, cloud, PKI) | Rotation via Lambda |
| Encryption service | Transit engine | KMS integration |
| Cost | Free (OSS) or HCP pricing | $0.40/secret/month + API calls |
| Complexity | High (dedicated infra) | Low (managed service) |
| Audit | Full audit log | CloudTrail |
| K8s integration | CSI driver, injector | ESO, CSI driver |
When to Use Vault
- Multi-cloud: Vault serves secrets to AWS, Azure, GCP, Kubernetes, and on-premises
- Dynamic secrets: Generate short-lived database credentials, AWS IAM tokens, TLS certificates
- Encryption as a service: Transit engine for application-level encryption without managing keys
- Advanced policies: Path-based ACLs, Sentinel policies, namespace isolation
When to Use AWS Secrets Manager
- AWS-only: If everything runs on AWS, Secrets Manager is the simplest choice
- Zero maintenance: Fully managed — no infrastructure to operate
- Lambda rotation: Automatic rotation for RDS, Redshift, and DocumentDB credentials
- IAM integration: Native AWS IAM policies for access control
Consider Also
- AWS Parameter Store: Free for standard parameters, good for configuration (not just secrets)
- External Secrets Operator: Syncs from any secret store (Vault, AWS SM, Azure KV) into K8s Secrets
My Recommendation
Use AWS Secrets Manager for AWS-only workloads where simplicity matters. Use Vault for multi-cloud, dynamic secrets, or encryption-as-a-service requirements. Book a consultation to design your secrets management architecture.
