Why AWS S3 Egress Fees Can Turn a $2 Storage Bill Into $180+

Cloud storage on platforms like AWS S3 appears inexpensive at roughly $0.023 per GB per month, but a separate charge called egress — applied every time data leaves the provider's network — can dwarf storage costs. At approximately $0.09 per GB, egress fees accumulate rapidly because they are triggered by every user download, CDN cache miss, cross-region replication, backup export, and even failed transfer retry. A single popular file served to millions of users can generate terabytes of billable outbound traffic from one asset alone. Unlike storage costs, egress is not capped by how much data you hold but by how much you serve, making it difficult to predict from a pricing page. Developers and businesses are advised to model both storage and egress costs separately before choosing a provider, as the latter is often the dominant line item in real-world bills.