AWS Consolidated Billing Overview
- Consolidated billing enables consolidating payments from multiple AWS accounts (Linked Accounts) within the organization to a single account by designating it to be the Payer Account.
- Consolidate billing
- is strictly an accounting and billing feature.
- allows receiving a combined view of charges incurred by all the associated accounts as well as each of the accounts.
- is not a method for controlling accounts, or provisioning resources for accounts.
- Payer account is billed for all charges of the linked accounts.
- Each linked account is still an independent account in every other way
- Payer account cannot access data belonging to the linked account owners
- However, access to the Payer account users can be granted through Cross Account Access roles
- AWS limits work on the account level only and AWS support is per account only
Consolidated Billing Process
- Owner of the paying account simply needs to send a request to the account owner from the Consolidated Billing page.
- If the linked account owner accepts the request, the linked account becomes part of the consolidated bill.
- Process cannot be initated from the linked account
Consolidated Billing Scenarios
- Consolidated Billing can be applied to scenarios when you
- have multiple accounts and want to get a single bill and track each account's charges for e.g. multiple projects, each with its own AWS account or separate environments (Dev, Prod) within the same project
- have multiple cost centers to track.
- have acquired a project or company with its own existing AWS account and you want consolidated bill with your other AWS accounts.
Consolidated Billing Benefits
- One Bill
- A single bill with a combined view of AWS costs incurred by all accounts is generated
- Easy Tracking
- Detailed cost report & charges for each of the individual AWS accounts associated with the "paying account" can be easily tracked
- Combined Usage & Volume Discounts
- Charges might actually decrease because AWS combines usage from all the accounts to qualify you for volume pricing discounts
- Free Tier
- Customers that use Consolidated Billing to consolidate payment across multiple accounts will only have access to one free usage tier and it is not combined across accounts
Volume Pricing Discounts
- For billing purposes, AWS treats all the accounts on the consolidated bill as if they were one account.
- AWS combines the usage from all accounts to determine which volume pricing tiers to apply, giving you a lower overall price whenever possible.
Volume Discounts Example
- Example AWS Pricing - AWS charges $0.17/GB for the first 10 TB of data transfer out used, and $0.13/GB for the next 40 TB used that translates into $174.08 per TB for the first 10 TB, and $133.12 per TB for the next 40 TB
- Usage - Bob uses 8 TB of data transfer out during the month, and Susan uses 4 TB (for a total of 12 TB used).
- Actual Individual Bill - AWS would have charged Bob and Susan each $174.08 per TB for their usage, for a total of $2088.96
- Volume Discount Bill - Combined 12 TB total that Bob and Susan used, would cost the paying account ($174.08 * 10 TB) + ($133.12 * 2 TB) = $1740.80 + $266.24 = $2007.04
EC2 Reserved Instances
- All Linked accounts on a consolidated bill can receive the hourly cost benefit of EC2 Reserved Instances purchased by any other account
- Linked accounts receive the cost benefit from other's Reserved Instances only if instances are launched in the same Availability Zone where the Reserved Instances were purchased
- Capacity reservation only applies to the product platform, instance type, and Availability Zone specified in the purchase
- For e.g., Bob and Susan each have an account on Bob's consolidated bill. Susan has 5 Reserved Instances of the same type, and Bob has none. During one particular hour, Susan uses 3 instances and Bob uses 6, for a total of 9 instances used on Bob's consolidated bill. AWS will bill 5 as Reserved Instances, and the remaining 4 as normal instances.
Consolidated Billing Best Practices
- Paying account should be used solely for accounting and billing purposes
- Consolidated billing works best with Resource tagging, as tags are included in the detailed billing report, which enables cost to be analyzed and decomposed across multiple dimensions and aggregation levels.
- Paying account owners should secure their accounts by using MFA (multi-factor authentication) and a strong password