Optimize Long-Term Amazon S3 Backup Costs with AWS Backup’s New Warm Storage Tier

Organizations today face a pressing challenge: how to store growing volumes of backup data for long retention periods—months or even years—while managing costs effectively and maintaining strong security. Regulatory compliance, governance standards, and modern ransomware threats all require secure, tamper-resistant backups. But these requirements often clash with budget realities.

To address this, AWS Backup has introduced a new low-cost warm storage tier for Amazon S3 backups, enabling customers to reduce long-term storage costs by up to 30% while preserving full protection capabilities, performance, and operational integrity. As an official AWS partner, Softprom helps enterprises adopt AWS Backup tiering to optimize data protection strategies with minimal operational overhead.

Below, we outline how the warm tier works, how to enable it, and when it provides the greatest cost savings.

Introducing a Low-Cost Warm Storage Tier for Amazon S3 Backups

AWS Backup now provides a dedicated warm storage tier for S3 backup data that must be retained long term. Key benefits include:

• Up to 30% lower storage costs
• Same restore performance as the standard tier
• Full ransomware and immutability protection
• Compatibility with AWS Backup Vault Lock and audit controls
• Automatic, policy-based tiering

Backed-up S3 objects enter the standard tier first and may transition to the warm tier after at least 60 days in the vault (or a longer threshold you define). AWS evaluates eligibility once daily, applying a small, one-time transition fee per 1,000 objects moved.

This setup allows organizations to preserve long-term backups without paying full production-tier prices—all while maintaining security, compliance, and operational continuity.

How AWS Backup S3 Tiering Works

AWS Backup S3 tiering follows several operational principles:

Daily eligibility evaluation

Once per day, AWS checks whether objects meet the minimum age threshold (60+ days) and automatically transitions eligible data.

No direct writes to warm tier

All new data initially lands in the standard tier and transitions only when eligible.

Flexible, vault-level configuration

Tiering can be enabled for:

• All S3 backups in all vaults
• A single vault
• Specific S3 buckets within a vault

More specific configurations override broader ones.

Safe transitions that preserve protection

All features remain unchanged, including:

• Ransomware protection
• Point-in-time recovery
• Vault Lock
• Search and item-level restore
• Logically air-gapped vaults
• Restore testing workflows

Cross-account and cross-Region copies

Copies always land in the standard tier of the destination vault. The destination vault’s rules determine when they become tiering-eligible.

Pricing Model and Cost Savings

The warm storage tier introduces a simple optimization model:

1. Lower storage price

Warm tier storage is approximately 30% cheaper than standard tier storage (e.g., $0.035 vs. $0.05 per GB-month in some Regions).

2. One-time transition fee

A nominal charge of ~$0.01 per 1,000 objects as they move to warm storage.

Best Practices for Using the Warm Storage Tier

When to use warm tiering

• Long-term retention (compliance, governance, industry regulations)
• Data lakes or analytics archives with stable, long-lived objects
• Backup datasets with low churn and predictable growth

Where caution is needed

High-churn datasets

Objects deleted or replaced within 60 days will not benefit.

Very small objects

Objects under 128 KB are billed as 128 KB in warm tier. For billions of small objects, evaluate the one-time transition fee.

How to maximize value

• Use S3 Storage Lens to analyze object age distributions.
• Start with a pilot on one S3 bucket.
• Monitor billing to confirm savings.
• Adjust thresholds based on retention and recovery patterns.

Conclusion

The AWS Backup warm storage tier is a powerful enhancement for cost-efficient, long-term data protection. Organizations can reduce backup storage costs by up to 30% while maintaining enterprise-grade resilience, ransomware protection, and compliance.

With automatic tiering, minimal operational overhead, and full compatibility with existing AWS Backup features, the warm tier enables teams to optimize long-term retention without sacrificing security or visibility.

As data volumes and retention demands continue to rise, this capability allows companies to meet regulatory and operational requirements—while strategically managing cloud storage costs.

As an official AWS partner, Softprom supports customers in evaluating, configuring, and operationalizing AWS Backup tiering to ensure maximum efficiency and protection.