EC2 Purchase Options

Here are all the main options:

On-Demand Instances

• Pay by the hour/second with no commitment

• Most flexible but most expensive

• Best for short-term, unpredictable workloads

• No upfront costs or contracts

Reserved Instances (RI)

• Commit to 1 or 3 years for significant discounts (up to 72%)

• Three payment options:

  • All upfront (highest discount)

  • Partial upfront

  • No upfront (lowest discount)

• Best for steady, predictable workloads

Savings Plans

• Newer, more flexible version of RIs

• Commit to hourly spend for 1 or 3 years

• More flexible than RIs as they work across:

  • Different instance types

  • AWS regions

  • EC2, Lambda, and Fargate

Spot Instances/Fleet

• Up to 90% discount

• Can be interrupted

• Best for flexible, fault-tolerant workloads

Dedicated Hosts

• Physical servers dedicated to your use

• Most expensive option

• Used for:

  • Compliance requirements

  • License management (like Oracle licenses)

  • Legacy server-bound software licenses

Capacity Reservations

• Reserve capacity in specific AZ

• Pay On-Demand rates

• No discount but guarantees availability

• Good for short-term, capacity-critical workloads