In Part 30 of the AWS SAA-C03 exam prep series, we break down the cost optimization strategies using Savings Plans, Reserved Instances, and Spot Instances. This guide helps you understand key differences and when to use each option to pass the Solutions Architect Associate exam in 2026.
Savings Plans vs. Reserved Instances
- Savings Plans offer flexible pricing across compute services (EC2, Lambda, Fargate) in exchange for a 1- or 3-year commitment to a consistent amount of compute usage ($/hour).
- Reserved Instances provide discounted capacity for specific EC2 instance families in a particular region or availability zone, with Standard or Convertible options.
Spot Instances Strategy
- Spot Instances use spare AWS capacity for up to 90% savings but can be terminated with a 2-minute warning. They are ideal for fault-tolerant workloads, batch processing, or stateless applications. Use Spot Fleet or EC2 Auto Scaling with mixed instances to maintain availability.
Exam Tips
- For steady-state, predictable workloads: Reserved Instances or Savings Plans (compute or EC2).
- For flexible, container-based or serverless workloads: Compute Savings Plans.
- For cost-sensitive, interruptible tasks: Spot Instances combined with On-Demand fallback.
Master these strategies to reduce AWS costs and ace the cost optimization domain of the SAA-C03 exam.