Comparisons / S3 Storage Classes
Storage

S3 Storage Classes

S3 offers multiple storage classes based on access frequency. The less frequently you access data, the lower the storage cost, but minimum storage duration, retrieval fees, and retrieval time all increase.

AspectS3 StandardS3 Intelligent-TieringS3 Standard-IAS3 Glacier Instant RetrievalS3 Glacier Flexible RetrievalS3 Glacier Deep Archive
Access frequencyFrequentUnknown or changingInfrequent (about monthly)Rare, but needs immediate accessRare (a few times/year)Almost never
Min. storage durationNoneNone for Frequent, Infrequent, and Archive Instant Access tiers30 days90 days90 days180 days
Retrieval timeImmediateImmediate (optional Archive tiers are asynchronous)ImmediateImmediateMinutes to 12 hours9–48 hours
Retrieval feeNoneNone for Frequent and Infrequent tiers (monitoring fee applies)Per GBPer GBPer request + per GBSame, with the lowest storage cost
Typical useActive web contentData with unpredictable access patternsBackups, DRArchives needing instant access, such as medical images or media assetsLong-term archive, complianceRegulatory/long-term audit logs

How to Choose

When access frequency is predictable, use lifecycle rules to transition Standard → IA → Glacier automatically. For irregular, unpredictable access patterns, use S3 Intelligent-Tiering to auto-optimize cost (for a small monitoring fee). Before moving infrequently accessed data into a class with a minimum storage duration like Standard-IA, confirm it won't be deleted or overwritten within that window — you're billed for the minimum duration even if deleted early.

Exam Points

  • SAA frequently tests "access frequency unknown" → Intelligent-Tiering, and "might be deleted within 30 days" → Standard-IA is unsuitable
  • Automatic tiering via lifecycle policies for cost optimization is a recurring SAA/SAP theme
  • One Zone-IA stores data in a single AZ, which can be unsuitable depending on availability requirements — a common exam trap

Related Service Guides

Last updated: 2026-09-06

This page is created from AWS official documentation and reviewed/edited by the operator. See our editorial & quality policy for details.