Why doesn't my Science Cloud balance match my AWS Cost Explorer dashboard?
A common question from Principal Investigators is why the costs shown in cloud provider dashboards (like AWS) differ from their official Science Cloud balances.
Native cloud dashboards only show estimated base pricing. They completely omit the Enterprise Support fees NASA pays, and they do not factor in NASA's negotiated discounts, special pricing agreements, or contract‑dependent adjustments. Because of this, relying on AWS Cost Explorer can result in variances of 10% or more, which could cause you to falsely predict a budget shortfall.
How the Science Cloud Calculates Actual Costs
Cost accuracy in the Science Cloud is maintained through a monthly reconciliation with ARC’s officially verified cost reports. However, because ARC data takes time to process, there is a built-in reporting lag:
- The One‑Month Lag: ARC's verified data lags by one month. To bridge this gap, FinOps publishes interim cost estimates for your most recent month, which are then officially reconciled the following month. Any numbers that have not yet been verified by ARC are explicitly marked as
(estimate)in your toolkit. - Current‑Month Adjustments: Some pricing adjustments depend on your total monthly volume. These cannot be finalized until the month ends, so they are estimated based on your projected usage until actuals are received.
Reading Your Cloud Account Balances
Your dashboard balance includes only the funds obligated directly to your cloud contract. It does not include the CCS overhead fees, as those are tracked separately. ARC automatically updates your balance in the toolkit whenever new obligations occur, and they occasionally send interim notices mid‑cycle that will immediately refresh your balance.
What are Expected Funds?
Actual Presented Costs vs. Cloud Estimates
While commercial cloud providers offer cost exploration tools, these displayed costs should be treated as estimates only. Discrepancies occur because native cloud dashboards do not account for:
- Enterprise support costs
- Special pricing agreements or negotiated discounts
- Dynamic pricing adjustments based on volume usage
Relying on these estimates can lead to variances of ~10% (and sometimes more), which could force premature project shutdowns due to falsely predicted budget shortfalls. To prevent this, the Science Cloud provides fully accurate cost reporting by incorporating all actual discounts, refunds, and overhead from official NASA invoices.
How Cost Accuracy is Maintained (The Reporting Lag)
The Science Cloud maintains accurate cost reporting through monthly reconciliation with ARC's official reports. However, because ARC's reports lag by one month, a verification gap exists.
- Example: When Science Cloud publishes August costs in early September, ARC has only verified data through July. The team relies on estimates for August.
- Reconciliation: Unverified costs are marked as
(estimate)and are reconciled once actual totals are known the following month (e.g., August estimates are verified in October).
Understanding Cloud Account Balances
Cloud account balance reports (funding minus costs) reflect only funds obligated to the cloud contract, excluding overhead expenses (which are obligated separately to the overhead contract).
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If a fund transfer misses the mid-month processing deadline, it
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will appear as
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"Expected."
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This
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serves as a visible reminder that a
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Detailed Cost Views
Summary views alone don't provide enough detail to understand cost drivers. The FinOps toolkit allows you to view costs by specific categories:
- Linked Account Name (The specific AWS account)
- Product/Service Name (e.g., S3, EC2, Lambda)
- Seller (AWS direct vs. AWS Marketplace)
- Usage Type (e.g., data transfer, compute hours)
- Usage Quantity (Volume of resources consumed)
Filtering by Cost Tags: You can filter views to answer specific questions, such as "How much did this user spend on this specific project?"
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transfer is in progress, but these funds are not included in your available balance. If Expected funds remain unresolved for an extended period of time, it usually indicates an administrative issue with the transfer that requires your attention.