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Elastic Compute Service:Storage capacity units

Last Updated:Nov 29, 2023

Storage capacity units (SCUs) are subscription storage resource plans that can be used to offset the pay-as-you-go bills of various storage resources. This topic describes the billing methods and refund rules of SCUs.


SCUs use the subscription billing method and are billed based on their capacity and validity periods. SCUs support only the All Upfront payment option. You must make a full payment at purchase. The following formula is used to calculate the amount that you need to pay upfront for an SCU:

Amount = SCU price × Validity period

  • SCU price: Go to the Pricing tab of the Elastic Compute Service product page to view the SCU price schedule.

  • Validity period: You select a period of one month, two months, three months, six months, one year, three years, or five years as the validity period for an SCU. You can receive some discounts for SCUs with a validity period of one or more years.

For example, if you want to buy a 2-month, 100-GB SCU in the China (Beijing) region and the price of 100-GB SCUs is USD 23 USD per month, you need to pay the amount upfront that is calculated by using the following formula:

Amount = USD 23 per month × 2 months = USD 46

After you purchase an SCU in a region, the SCU automatically matches eligible pay-as-you-go storage resources in the region to offset bills. For information about how SCUs are applied to offset the bills of pay-as-you-go storage resources, see Usage rules.


After an SCU expires, you cannot use it to offset the bills of pay-as-you-go storage resources. If you have no other SCUs in the same region as the expired SCU, the pay-as-you-go storage resources are billed on a pay-as-you-go basis.

Renewal or upgrade

SCUs cannot be renewed or upgraded. You can purchase multiple SCUs based on your storage usage.

  • If an SCU cannot cover all the bills of pay-as-you-go storage resources, you can purchase more SCUs.

  • If an SCU is about to expire, you can purchase more SCUs and specify a time for them to take effect.

For information about how to purchase an SCU, see Purchase an SCU.