This topic describes how to purchase reserved instances in the ECS console.


  • Before you purchase reserved instances, make sure that the pay-as-you-go instances you want to match meet the requirements for applying reserved instances. For more information, see the Limits section of Reserved instance overview.
  • You cannot manually manage how reserved instances and pay-as-you-go instances are matched. Ensure that you understand the matching rules for reserved instances. For more information, see Matching rules of RIs.


  1. Log on to the ECS console.
  2. In the left-side navigation pane, choose Instances & Images > Reserved Instances.
  3. In the top navigation bar, select a region.
  4. Click Purchase Reserved Instance.
  5. Configure the region-related parameters.
    1. Select a region.
    2. Set Resource Reservation.
      Note Only zonal reserved instances support resource reservation. Regional reserved instances apply to pay-as-you-go instances of different sizes in different zones within the same region.
    3. Select a zone from the Zone drop-down list.
  6. Configure the instance-related parameters.
    1. Select an instance type.
      Note You must select an instance size when you purchase a regional reserved instance. The regional reserved instance can match any pay-as-you-go instances of the specified instance family within the specified region regardless of size.
    2. Set Operating System Platform.
      You can select Linux or Windows.
      Note The reserved instance only matches pay-as-you-go instances that use the selected type of operating system. The operating system of an reserved instance cannot be changed after you purchase it.

      To apply a reserved instance to pay-as-you-go instances created from Bring Your Own License (BYOL) images, submit a ticket.

    3. Set Payment Option.
      All Upfront, Partial Upfront, and No Upfront are available. For more information, see Reserved instance billing.
  7. Configure purchase-related parameters.
    1. Optional:Specify the Name parameter.
    2. Specify the Term parameter.
      You can select 1 Year or 3 Years.
    3. Specify the Instance Count parameter.
      The reserved instance can match the specified number of pay-as-you-go instances of the specified instance type. For example, if the instance type is ecs.g5.large and Instance Count is set to 3, the reserved instance can match three pay-as-you-go instances of the ecs.g5.large instance type.
  8. Read and select ECS Terms of Service and click Purchase.
  9. In the dialog box that appears, confirm that the parameters are correct and click Create Order.
  10. Read the payment information and then click Pay.


After you purchase a reserved instance, you can immediately apply billing discounts when the reserved instance matches one or more pay-as-you-go instances. You can also manage reserved instances in response to pay-as-you-go instance changes.