Study guide
Technical reference and lesson notes
Purpose of This Lesson
AWS Budgets helps organizations define expected AWS spending or usage and receive notifications when actual or forecasted consumption reaches configured thresholds. It is primarily a visibility and alerting service: it helps teams detect unexpected costs, review resource usage, and adjust financial expectations before the end of a billing period.
Key Concepts
Cost and Usage Budgets
AWS Budgets can monitor several dimensions of AWS consumption:
- Cost budgets: Track spending against a monetary threshold, such as a monthly budget of
$10,000. - Usage budgets: Track service usage rather than its direct cost.
- Reservation budgets: Track Reserved Instance utilization and coverage.
- Savings Plans budgets: Track Savings Plans utilization and coverage.
A budget can generally be configured for a recurring period, such as monthly, and can use a fixed or otherwise defined budget amount depending on the configuration.
Actual Versus Forecasted Spend
Budget alerts can be based on two different measurements:
- Actual spend: Notifies when recorded spending reaches the configured threshold.
- Forecasted spend: Notifies when AWS predicts that spending will reach the threshold by the end of the budget period.
For example, a monthly budget of $100 with an 80% forecast threshold can generate an alert if projected monthly spending reaches $80, even if current spending is still below that amount. This is useful for identifying a potentially expensive resource early in the billing cycle.
Forecast-based alerts require careful interpretation. A forecast is an estimate, not a guarantee. The alert may be appropriate even when the workload is intentionally temporary, such as a large instance used for a short-lived test.
Notifications and Reports
AWS Budgets supports notifications to configured recipients when a threshold is reached. Notifications can be associated with actual or forecasted values and may be configured at different threshold percentages.
Budget reports provide periodic budget information and can be configured for delivery on a daily, weekly, or monthly schedule. Reports are useful when stakeholders need recurring visibility rather than only exception-based alerts.
Related AWS Services
AWS Budgets works with other AWS cost-management and operations tools, including:
- AWS Cost Explorer: Investigate the detailed cost and usage behind a budget alert.
- AWS Chatbot: Deliver notifications to supported chat and collaboration channels.
- AWS Service Catalog: Integrate financial controls and governance with approved product provisioning workflows.
A practical workflow is to use Budgets for threshold detection and Cost Explorer for investigation and attribution.
Exam-Relevant Takeaways
- AWS Budgets is used to define custom cost, usage, reservation, or Savings Plans thresholds.
- Alerts can be based on actual consumption or forecasted consumption.
- Forecast alerts are proactive; they can trigger before the budget has actually been exceeded.
- A budget notification is not the same as a hard spending cap or automatic resource shutdown.
- Budget periods can be recurring, such as monthly.
- Reservation budgets help evaluate Reserved Instance utilization and coverage.
- Savings Plans budgets help evaluate Savings Plans utilization and coverage.
- Budget data may not appear immediately after a budget is created; AWS needs time to populate and evaluate billing information.
- Use Cost Explorer when the requirement is to analyze which services, accounts, regions, or usage patterns caused the spending.
Architecture Decision Guide
| Requirement | Appropriate capability | Important consideration |
|---|---|---|
| Alert when monthly AWS spending reaches a threshold | Cost budget | Choose actual, forecasted, or both as appropriate |
| Detect likely overspending before month-end | Forecasted cost alert | Forecasts are estimates and can change |
| Track a non-cost consumption limit | Usage budget | Select the relevant usage dimension |
| Determine whether Reserved Instances are being used effectively | Reservation budget | Focuses on utilization and coverage |
| Monitor Savings Plans performance | Savings Plans budget | Helps identify underutilization or insufficient coverage |
| Send periodic financial summaries | Budget report | Configure daily, weekly, or monthly delivery |
| Investigate the source of an alert | Cost Explorer | Budgets identifies the threshold event; Cost Explorer supports deeper analysis |
| Enforce a strict spending limit | Budget alone is insufficient | Add governance, permissions, automation, and resource controls |
Common Exam Traps
- Assuming AWS Budgets prevents spending: Budgets normally provides monitoring and notifications. It does not inherently stop all charges when a threshold is crossed.
- Confusing actual and forecasted alerts: An actual alert reflects recorded spend. A forecasted alert reflects predicted end-of-period spend.
- Treating a forecast as a fixed commitment: Forecast results can change as usage patterns change.
- Using Budgets for detailed cost attribution: Cost Explorer and billing-data analysis are more appropriate for determining the exact cause of increased spending.
- Expecting immediate data after creation: Newly created budgets may initially show little or no data while billing information is collected and processed.
- Confusing cost budgets with usage budgets: A usage threshold measures consumption units; a cost budget measures monetary spend.
- Assuming a reservation budget is a reservation purchase mechanism: Reservation budgets monitor utilization and coverage; they are not themselves a purchasing strategy.
Real-World Engineer Notes
- Set an early forecast threshold, such as 50% or 80%, for development and sandbox accounts so teams have time to investigate.
- Use multiple budgets for different scopes, such as an organization, account, environment, project, or service category where the billing configuration supports those dimensions.
- Pair notifications with an operational response: identify the owner, inspect Cost Explorer, check recent deployments, and verify whether the spending is intentional.
- Separate informational alerts from escalation alerts. A lower threshold can notify the engineering team, while a higher threshold can notify finance or platform operations.
- Temporary high-cost workloads can legitimately trigger forecast alerts. Document expected exceptions rather than automatically assuming every alert indicates a defect.
- For stronger financial governance, combine Budgets with AWS Organizations controls, IAM permissions, tagging and allocation standards, approval workflows, and carefully designed automation.
Quick Reference Summary
- Service: AWS Budgets
- Primary purpose: Monitor AWS cost or usage against custom thresholds
- Budget types: Cost, usage, reservation, and Savings Plans
- Alert measurements: Actual and forecasted
- Scheduling: Recurring periods such as monthly; budget reports can be daily, weekly, or monthly
- Useful integrations: Cost Explorer, AWS Chatbot, and AWS Service Catalog
- Core limitation: A budget alert is not automatically a hard spending restriction
- Investigation tool: AWS Cost Explorer
Flashcards
- Q: What is the primary purpose of AWS Budgets?
A: To define cost or usage thresholds and notify users when actual or forecasted consumption reaches them.
- Q: What is the difference between an actual and a forecasted budget alert?
A: An actual alert is based on recorded consumption; a forecasted alert is based on predicted consumption for the budget period.
- Q: Which AWS Budgets type monitors monetary spending?
A: A cost budget.
- Q: Which AWS Budgets type monitors consumption rather than dollars?
A: A usage budget.
- Q: What does a reservation budget help track?
A: Reserved Instance utilization and coverage.
- Q: What does a Savings Plans budget help track?
A: Savings Plans utilization and coverage.
- Q: Which service can be used to investigate the detailed source of a budget alert?
A: AWS Cost Explorer.
- Q: Can AWS Budgets normally stop all AWS resources when a threshold is crossed?
A: No. Budgets primarily provides monitoring and notifications; enforcement requires additional controls or automation.
- Q: Why might a newly created budget initially show no data?
A: Billing data needs time to populate and be evaluated.
- Q: What is the purpose of a budget report?
A: To deliver scheduled budget information to configured recipients.
- Q: When is a forecasted alert especially useful?
A: When a team wants early warning that current usage is likely to exceed the budget by the end of the period.
- Q: Name two services that can integrate with AWS Budgets for notifications or governance workflows.
A: AWS Chatbot and AWS Service Catalog; Cost Explorer is also a related cost-management integration.
Practice Questions
Question 1
A company wants to be notified as soon as AWS predicts that its monthly spending will exceed 80% of the approved budget. Current spending is only 45% of the budget, but a recently launched workload is expected to run throughout the month. Which AWS Budgets configuration meets this requirement?
A. An actual cost alert at 80%
B. A forecasted cost alert at 80%
C. A usage budget at 80%
D. A reservation utilization alert at 80%
Correct answer: B. A forecasted cost alert evaluates predicted spending for the budget period and can notify the company before actual spending reaches the threshold.
Question 2
A platform team receives an AWS Budgets alert and needs to identify which service and account caused the increase. Which service should the team primarily use for this investigation?
A. AWS Cost Explorer
B. AWS Service Catalog
C. AWS Chatbot
D. AWS Budgets reports only
Correct answer: A. AWS Cost Explorer provides detailed cost and usage analysis. Budgets detects the threshold condition, while Cost Explorer helps investigate its source.
Question 3
A finance department wants to monitor whether Reserved Instances are being used effectively and whether workloads have sufficient reservation coverage. Which budget type should it configure?
A. Cost budget
B. Usage budget
C. Reservation budget
D. Savings Plans budget
Correct answer: C. Reservation budgets are designed to track Reserved Instance utilization and coverage.
Question 4
A development account must never incur more than a fixed dollar amount. The architect proposes creating an AWS Budgets cost budget and treating its alert as a hard spending limit. Which statement is most accurate?
A. The budget automatically blocks all charges after the threshold is reached.
B. The budget automatically terminates every resource in the account.
C. The budget provides threshold notifications, but additional governance or automation is needed for enforcement.
D. The budget converts all resources to the lowest-cost configuration.
Correct answer: C. AWS Budgets is primarily a monitoring and notification capability. Strict enforcement requires additional controls, permissions, policies, or automation.
Question 5
An organization wants a recurring summary of budget status delivered to stakeholders every week. Which AWS Budgets feature should it use?
A. A weekly budget report
B. A forecasted threshold only
C. A usage budget with an actual alert
D. Cost Explorer saved searches only
Correct answer: A. Budget reports can be configured for scheduled delivery, including weekly delivery.