Understanding AWS S3 and Its Storage Classes
What is AWS S3?
Amazon S3 (Simple Storage Service) is AWS’s core storage service, offering highly available, durable, and scalable object storage. Whether you’re hosting website images, videos, backup files, or raw analytics data, S3 provides a reliable way to store and retrieve your data.
Key features include versioning, multi-region redundancy, integration with IAM for access control, and seamless connection to CloudFront (AWS’s CDN)—making it one of the most popular entry points for enterprises moving to the cloud.
AWS S3 Storage Classes (Pricing by Use Case)
S3 pricing depends on the storage class you choose, with each class optimized for different data access patterns and retention needs:
| Storage Class | Characteristics Use Cases |
|---|---|
| S3 Standard | Designed for frequently accessed hot data, such as website images and static application content. |
| S3 Intelligent-Tiering | Automatically moves data between tiers based on access patterns; ideal for unpredictable workloads. |
| S3 Standard-IA | Infrequent Access, ideal for backups and disaster recovery. |
| S3 One Zone-IA | Similar to Standard-IA, but stored in a single AZ, lower cost but higher risk. |
| S3 Glacier Instant Retrieval | For cold storage that still requires millisecond access. |
| S3 Glacier Flexible Retrieval | Hours-level retrieval, suited for archival data. |
| S3 Glacier Deep Archive | Lowest-cost option, designed for long-term archival data rarely retrieved. |
✅ Choosing the right storage class not only impacts your AWS S3 costs, but also affects data retrieval speed and access strategy. To explore all available options, check out: Amazon S3 Storage Classes
AWS S3 Main Pricing Components
AWS S3 pricing is divided into four main categories: storage costs, request and retrieval costs, data transfer costs, and other additional charges (such as early deletion fees, versioning, and management features). These costs vary depending on usage, so it’s recommended to select the right storage class and usage strategy based on your actual needs. Since AWS does not currently operate a data center in Taiwan, this article uses the Hong Kong region as an example for pricing.
1. Storage Costs
Storage costs may vary depending on the chosen storage class and total storage volume. The price per GB is different based on your selection:
| Storage Class | Price (per GB/month) | Notes |
|---|---|---|
| Standard | ~ $0.023 (up to 500TB/month) | Best for frequently accessed data. |
| Standard-IA | ~ $0.0138 | Suitable for infrequently accessed data that still requires fast retrieval. |
| Glacier Instant | ~ $0.005 | Cold storage backup with instant retrieval. |
| Glacier Deep Archive | ~ $0.002 | Longest retrieval time, lowest-cost option for rarely accessed data. |
2. Request and Retrieval Costs
Different operations are billed based on the storage class and number of requests. Using S3 Standard as an example, common pricing is as follows:
| Operation Type | Price (per 1,000 requests) | Notes |
|---|---|---|
| GET、SELECT、List | $0.0004 | Read objects/files |
| PUT、COPY、POST | $0.005 | Write or replicate |
3. Data Transfer Costs
- Data In: Free
- Uploading data from the internet into S3 is free of charge.
- Data Out to the Internet: Usage-based pricing. The first 100GB per month is free (this applies across all AWS services, shared across regions).
| Transfer Volume | Price (per GB) |
|---|---|
| First 100 GB/month | Free |
| Next 10 TB/month | $0.12 |
| Next 40 TB/month | $0.085 |
| Next 100 TB/month | $0.082 |
| Over 150 TB/month | $0.08 |
- Internal S3 transfers are free (e.g., transfers between EC2 and S3 within the same region).
4. Other Potential Charges
- S3 Lifecycle – Costs for lifecycle rule executions
- S3 Replication – Data transfer and additional storage for replication
- S3 Inventory – Report generation and storage fees
AWS S3 Cost Calculation Example
Suppose you store 1TB of images in S3, and each month you generate:
- 1,000,000 GET requests
- 110GB of data transfer out to the Internet
| Item | Quantity | Unit Price | Estimated Cost |
|---|---|---|---|
| Storage (Standard) | 1,000 GB | $0.025/GB | $25.00 |
| GET Requests | 1,000,000 reqs | $0.0004 per 1,000 requests | $0.40 |
| Data Transfer Out | 110 GB | $0.12/GB (first 100GB free) | $1.20 |
| Total | $26.60 / month |
Cost-Saving Strategies for AWS S3
- Use Lifecycle Policies for Cold Data
- Automatically transition objects after 30 days to Standard-IA, and after 90 days to Glacier or Deep Archive.
- Combine with S3 Storage Class Analysis to identify underutilized objects.
- Reduce Request Costs
- Consolidate small files into larger objects (e.g., tar/gzip).
- Batch process JSON/CSV to minimize PUT/GET calls.
- Use CDN to Reduce S3 Data Transfer Costs
- By using AWS CloudFront as a front-end CDN, frequently accessed resources can be cached at edge locations, significantly reducing data transfer from S3.
- CloudFront’s own data transfer rates are generally cheaper than direct S3 transfer, while also providing the benefit of lower latency.
- Be Cautious with Cross-Region Replication
- Enabling cross-region S3 Replication (e.g., replicating from Tokyo to Sydney) will generate storage costs in both regions, and replication traffic will also be billed.
- Unless required for regulatory compliance or disaster recovery, it is recommended to avoid cross-region replication, or instead use same-region replication with multi-AZ redundancy.
- Cross-region S3 Replication incurs both replication traffic charges and additional storage costs.
Important Notes for Taiwan Users: Taxes and Currency
If you pay AWS directly with an official AWS account, costs are considered overseas expenses in Taiwan:
- +20% foreign transaction tax
- Exchange rate fluctuations
By purchasing AWS resources through a local cloud reseller, you can:
- Get official Taiwan invoices
- Avoid foreign transaction tax
- Potentially enjoy discounted rates
✅ Elite Cloud offers free S3 cost analysis and optimization consulting, helping you legally reduce expenses.
Conclusion: Master the Pricing to Master AWS S3
AWS S3 is powerful and flexible, but its billing system is complex. From storage classes to requests, from data transfer to lifecycle rules, every detail matters for your final bill.
👉 Want to know if your current AWS S3 costs are too high? Or see if reseller pricing offers you a better deal? Contact us today for a free consultation and cost analysis.
