Reserved Capacity

Purchase 1 or 3-year capacity commitments for provisioned tables to save up to 77% on throughput costs.

What is DynamoDB reserved capacity?

Reserved capacity allows you to purchase a commitment to a minimum amount of DynamoDB provisioned capacity in exchange for significant discounts.1 By committing to use a specific amount of read or write capacity for a 1-year or 3-year term, you can reduce your hourly capacity costs by up to 77%.

Key characteristics:

  • Available for provisioned mode only - Not compatible with on-demand tables
  • Standard table class only - Not available for Standard-IA tables1
  • Significant discounts - Up to 54% (1-year) or 77% (3-year)
  • Regional and account-scoped - Cannot be transferred between regions, but shares across linked accounts with consolidated billing
  • Automatic application - AWS billing automatically applies reservations to minimize costs across organization
  • Binding commitment - Cannot be canceled or refunded

Pricing and discounts

Reserved capacity offers two term options with different discount levels:1

TermPayment ModelDiscount
1 yearPartial upfrontUp to 54% off standard provisioned rates
3 yearPartial upfrontUp to 77% off standard provisioned rates

Purchase details:

  • Minimum allocation: 100 capacity units (RCUs or WCUs)
  • Payment structure: One-time partial upfront payment + discounted hourly rate
  • Billing: You’re billed for the entire committed capacity whether you use it or not
  • Excess capacity: Any capacity beyond your reservation is billed at standard provisioned rates

How savings are calculated

When you purchase reserved capacity, you receive:

  1. Upfront discount - Lower initial payment compared to on-demand equivalent
  2. Hourly discount - Reduced per-hour rate for the reserved capacity
  3. Guaranteed cost - Predictable billing for the term regardless of AWS price changes

Consolidated billing and AWS Organizations

Reserved capacity automatically shares across linked accounts when using consolidated billing in AWS Organizations:1

How it works:

  1. Purchase reserved capacity
  2. AWS billing first applies the reservation to the purchasing account
  3. Any unused reserved capacity is automatically applied to other linked accounts
  4. This happens automatically every billing hour with no configuration required

Important limitations:

  • Reserved capacity is region-specific - Cannot share across regions
  • Cannot be transferred or sold to accounts outside your organization

Resources

Footnotes

  1. DynamoDB reserved capacity ↩ ↩2 ↩3 ↩4