Overview

CSS provides two billing modes: yearly/monthly and pay-per-use to meet your requirements in different scenarios.

Yearly/Monthly is a prepaid billing. You pay in advance for a subscription term, and in exchange, you get a discounted rate. The longer the subscription term, the bigger the discount. This mode is a good option for long-term, stable services.
Pay-per-use is a postpaid billing mode. You pay as you go and just pay for what you use. The cluster usage is calculated by the second but billed every hour. This mode allows you to adjust resource usage easily. You do not need to prepare resources in advance, and will not have excessive or insufficient preset resources.

**Table 1** Billing modes
Billing Mode	Yearly/Monthly	Pay-per-use
Payment Method	Prepaid Billed by the subscription term you purchase	Postpaid Billed by your actual usage duration
Billed Usage Period	Billed by the subscription term you purchase	Billed by second and settled by hour
Billing Item	Node specifications (vCPUs and memory), node storage, and public network bandwidth	Node specifications (vCPUs and memory), node storage, and public network bandwidth
Billing Mode Change	Yearly/Monthly can be changed to pay-per-use. The change takes effect only after the yearly/monthly subscription expires. For details, see From Yearly/Monthly to Pay-per-Use.	Pay-per-use can be changed to yearly/monthly. For details, see Pay-per-Use to Yearly/Monthly. After you pay for the order, the yearly/monthly resources take effect immediately.
Specifications Change	Supported	Supported
Application Scenarios	This mode is cost-effective and suitable when the duration of resource usage is predictable. This mode is recommended for long-term users.	This mode is ideal when you want more flexibility and control on compute resource.