What are Cost and Usage Reports (AWS) ?

How AWS Cost and Usage Reports Work

The CUR process automates the collection and delivery of your detailed billing data.

1. Configuration: You enable and configure the CUR in the AWS Billing Console, specifying the report name, time granularity (hourly/daily/monthly), and data inclusions.
2. Data Generation: AWS automatically compiles your detailed usage and cost information from across all accounts and services.
3. Delivery: Daily, AWS delivers the report files directly to a designated Amazon S3 bucket that you own.
4. Processing: You then use other services like Amazon Athena, Amazon QuickSight, or a third-party tool to query, analyze, and visualize the data.
5. Automation: The entire pipeline, from generation to delivery, is fully managed and automated by AWS.

Automated workflow ensures you always have access to the most detailed and up-to-date financial data for in-depth analysis.

Key Components of AWS Cost and Usage Reports

The CUR's structure contains numerous fields that provide a multi-dimensional view of spending.

1. Identity Metadata: Includes details like bill_billing_entity and line_item_usage_account_id to identify the source of cost.
2. Time Period: Fields like line_item_usage_start_date provide the exact timing of the resource usage.
3. Resource Information: Includes IDs, types, and tags (resource_tags) to identify the specific resource incurring cost.
4. Pricing Data: Contains the actual cost (line_item_unblended_cost), negotiated rates, and pricing unit.
5. Usage Details: Specifies how much of a service was used (line_item_usage_amount) and the unit of measure.

These components work together to transform raw billing data into an analyzable resource for finance and engineering teams.

Benefits of AWS Cost and Usage Reports

Leveraging the CUR provides significant advantages for financial management and resource optimization.

1. Maximum Granularity: Offers the most detailed view of AWS costs and usage, down to the hourly level.
2. Cost Allocation: Enables precise chargeback/showback using resource tags and account IDs.
3. Custom Analysis: Serves as the single source of truth for building custom reports and dashboards.
4. Audit Compliance: Provides an immutable, detailed record of all spending for internal and external audits.
5. Optimization Insights: Reveals hidden cost drivers and waste that are invisible in summarized reports.

By providing this level of detail, the CUR empowers organizations to take full control of their cloud financial management.

Limitations of AWS Cost and Usage Reports

While powerful, the CUR has inherent characteristics that can be challenging.

1. Raw Data Dump: It is not a tool; it requires significant processing and analysis to extract insights.
2. Complexity: The sheer number of fields and data volume can be overwhelming for new users.
3. Processing Delay: Data is typically updated only once every 24 hours, not in real-time.
4. Setup Overhead: Requires configuring other services (S3, Athena) to be truly useful.
5. No Actionability: It provides data for analysis but does not itself offer recommendations or actions.

Understanding these limitations is key to building an effective FinOps pipeline around the CUR.

Difference Between AWS Cost and Usage Reports and AWS Cost Explorer

The CUR and Cost Explorer serve different but complementary purposes in cloud financial management.

When to Use AWS Cost and Usage Reports

The CUR is the tool of choice for specific, advanced use cases that require deep data manipulation.

1. Custom Chargeback: When you need to build a detailed, custom chargeback or showback model for internal teams.
2. Advanced Analysis: For performing complex, SQL-based analysis that isn't possible in standard tools.
3. Audit Trail: To create an immutable, detailed record of all costs for compliance and auditing purposes.
4. Third-Party Integration: When you need to feed granular, raw AWS cost data into a third-party FinOps tool.
5. Historical Trending: For building long-term, customized historical trend reports beyond the 12-month limit in Cost Explorer.

Choose the CUR when your analysis requires going beyond the capabilities of pre-built tools to work with the raw data itself. It is the foundation for a mature, data-driven cloud financial practice.

Frequently Asked Questions 

• Q1.Are AWS Cost and Usage Reports paid?

  No, generating the AWS Cost and Usage Report itself is a free service. However, you incur standard charges for the Amazon S3 storage used to hold the report files and for any services used to analyze them, like Amazon Athena.

• Q2. How often is the CUR updated?

  The CUR is typically updated at least once every 24 hours. It provides a comprehensive daily refresh of your cost and usage data, but it is not a real-time monitoring tool.

• Q3. What is the difference between CUR and a standard AWS bill?

  The standard bill is a high-level monthly invoice. The CUR is a granular, machine-readable data feed that breaks down costs by the hour or day, includes resource-level detail, and contains metadata like tags.

• Q4. Can I analyze the CUR without other AWS services?

  While you can download the files manually, analysis requires other tools. AWS provides native services like Amazon Athena and QuickSight to query and visualize the data effectively.

• Q5. How long does AWS keep my CUR data available?

  AWS delivers new report files daily, but you manage the retention policy on your S3 bucket. You control how long the historical data is stored and available for your analysis.