AWS adds IAM cost tracking to Bedrock via Athena and CUDOS dashboards

This post is the second in a series on Bedrock cost attribution. Part 1 introduced the core feature—automatic tracing of inference requests to IAM principals—but this follow-up focuses on the practical analysis layer: how to visualize and aggregate that data for operational use. The body positions two complementary tools: Amazon Athena (for SQL flexibility, BI tool integration, and custom chargeback logic) and CUDOS dashboards (for pre-built, organization-specific visuals). The critical prerequisite is enabling the "Include caller identity (IAM principal) allocation data" checkbox in CUR 2.0 configuration, which populates both the line_item_iam_principal column and IAM principal tags.

The post then walks through three progressively sophisticated Athena query patterns. The first isolates cost by caller and model usage type. The second groups by known IAM principal tags (team, project, cost center) to answer aggregate questions like "How much did engineering spend?" The third uses UNNEST to dynamically discover tag schemas across an organization—useful when tag names are unknown or evolve over time. A real-world example then shows how a platform team running multiple services (document processor, chatbot) can isolate spend per service using role-based filtering. AWS acknowledges that enabling IAM principal data increases CUR file sizes, placing the burden of storage planning on the operator.