The standard configuration for managing AWS accounts in the platform is under a shared consolidation model.
When there are multiple accounts under a single AWS payer account, your charges in the AWS console are reflective of volume discounts related to the combination of the other accounts under the same payer account. Volume discounts, especially when you’re looking at EC2, are reflective of reserved instances that may use the same instance types, availability zones, and regions you have setup in your AWS accounts.
For all of the AWS strengths, there is also a bit of complexity around Reserved Instances (RI) and Consolidated Billing. We (partner) often hear questions about how to effectively ensure that costs are properly tracked and allocated. Rather than looking for matching resources with an individual account, AWS automatically applies RI benefits to matching resources across all linked accounts. This is why you may see a different price in the AWS console vs. your statement from the platform. SES is the tool that keeps track of the volume and RI purchases and reports billing data accurately to individual linked accounts. Basically keeping the benefits to the accounts that made the investment in the RI purchases. As AWS references in its own communication when you participate in a blended rate scenario (which is the case working with us (partner) in order for you to take advantage of the platform and other (partner) services) you CANNOT use the native console for billing information. Usage information will be 100% aligned but billing data is impacted in the AWS console due to consolidation and blended rates as outlined below.
Here is a LINK from AWS that further explains the consolidated billing and how it affects billing information. Additionally here is a LINK to AWS that describes Blended Rates (which is the core issue regarding billing data differences in your (customer’s) console versus billing information viewed in the platform and the actual (partner) invoice. I have copied and highlighted a portion of the information which is vitally important to understand.
Blended Rates and Costs
Blended rates are the averaged rates of the Reserved Instances and On-Demand Instances that are used by member accounts in an organization in AWS Organizations. AWS calculates blended costs by multiplying the blended rate for each service with an account’s usage of that service. LINK
Understanding Consolidated Bills
If you manage an organization in AWS Organizations, you can use consolidated billing to view aggregated usage costs for accounts in the organization. Consolidated billing can also help you reduce those costs. For example, to ensure that you pay the lowest available prices for AWS products and services, AWS offers pricing tiers that reward higher usage with lower prices and discounted rates for purchasing instances in advance (known as reservations or Reserved Instances). Using consolidated billing, you can combine usage from multiple accounts into a single invoice, allowing you to reach the tiers with lower prices faster. You can also apply unused reservations from one account to another account's instance usage. LINK
Excerpt from the AWS website link above:
"Blended rates are the averaged rates of the Reserved Instances and On-Demand instances used by linked accounts. This section explains how AWS determines the blended rates for customers who use consolidated billing.
Note: Viewing billing information in the AWS billing console can show Blended Rates near some AWS service. The Blended Rate indicator is meant for display purposes only, and does not reflect the actual charges.
Here is how consolidated bills are calculated:
- A Reserved Instance is a capacity reservation. It is not a virtual machine. It is a commitment by a customer to pay in advance for specific Amazon EC2 or Amazon RDS instance capacity. In return, the customer gets a discounted rate over the cost of an On-Demand instance that is created or deleted in response to application load. From a technical perspective, there is no difference between a Reserved Instance and an On-Demand instance. When a customer launches an instance, AWS checks the account records for Reserved Instance purchases that can be applied to that instance.
- Consolidated Billing customers have multiple accounts that roll up into a single account that is designated as the payer account. This group of accounts is often called an account family. Owners of payer accounts see all usage incurred by the account family. This activity is aggregated to the payer account and then allocated to the linked accounts that generated the charge in proportion to the linked account's usage. In other words, the linked account line items that you see in AWS Cost and Usage report and monthly billing (hourly) reports and on the Account Activity page are calculated recursively: The charges are calculated at the payer level and then allocated to linked accounts. Blended rates appear only on linked account line items.”
ROUNDING IN BILLING REPORTS
- The usage report has to do rounding and its done to the 2 decimal points. The rounding is off of 9 + decimal points deep.
- DBR rounding occurs at the service level. DBR does all the fractional hours and fees.
- The Reseller billing report could be higher than the values received on your invoice from Tech Data.
- The billing represents the billing with rounded included.
- If you want to go to the penny you go to DBR view of the billing data.
- Usage report rounds and is dynamic. It could change at any time.
- The report that is post-billing statement generation maintains the view of billing at a specific month against the pricing at the time of the billing. When you run the same report for a past month, you are likely to see changes to the billing report.
The usage report that you view your usage detail from in SES takes data directly from the billing DBR however given that the billing detail goes in some cases to 9 and beyond decimal points we have to round the data when you view it in the report. The rounding for this view is occurring at the individual line item level and then rolled up. The reason for this is that you have drill down capabilities in the usage report to go into for example ec2-box usage-instance type. Because of this and the two decimal points that get displayed it forces rounding. The bill itself, however, is not rounded. It is calculated with all decimal points then totaled and at the service category total is then rounded to the nearest penny. To summarize the usage report view represents a rounded view of the bill because you have the ability to drill Deeper into the detail and because it is always displayed to 2 decimals points. The only way to reconcile your charge to "the penny" is to use the detailed billing file we provide with the bill aka the dbr. The usage report will always show a "rounded" view of the data.