You are charged for using Internet NAT gateways. This topic describes the billing method and billable items of Internet NAT gateways.

Billing overview

Billing of NAT gateways

Internet NAT gateways support the pay-as-you-go billing method.
Item Rule
Billing method Internet NAT gateways support the pay-as-you-go billing method. You are charged based on your resource usage. Bills are generated and fees are deducted from the balance of your Alibaba Cloud account at the end of each billing cycle.
Billing cycle and bill generation time Internet NAT gateways are billed based on resource usage on an hourly basis. Bills are generally generated one hour after a billing cycle ends. The time when bills are generated is determined by the system.
Billable item and billing formula The billable items of Internet NAT gateways consist of instances and Capacity Units (CUs).
Total fee = Instance fee + CU fee
Note After you delete an Internet NAT gateway, the billing immediately stops. For more information about how to delete an Internet NAT gateway, see Delete an Internet NAT gateway.

Specifications of NAT gateways

You can upgrade the specification of an Internet NAT gateway to improve performance. The following table describes the performance metrics of each specification:
Specification Maximum number of concurrent connections Maximum number of new connections Throughput
Default 2,000,000 100,000 5 Gbit/s to 15 Gbit/s (automatic scaling)
Maximum quota that you can apply for by submitting a ticket 10,000,000 1,000,000 100 Gbit/s

Instance fees

You are charged instance fees for Internet NAT gateways on an hourly basis. Fees are calculated and bills are generated on an hourly basis. If you use an Internet NAT gateway for less than 1 hour, the usage duration is rounded up to 1 hour. The usage duration refers to the period of time from when an Internet NAT gateway is created to when the Internet NAT gateway is released.

Instance fee = Unit price of an Internet NAT gateway(USD/hour) × Usage duration (hours)
The following table lists the unit prices of Internet NAT gateways.
Note The prices listed in the following table are for reference only. The actual prices on the buy page shall prevail.
Region Unit price(USD/hour)
China (Hangzhou), China (Shanghai), China (Qingdao), China (Beijing), China (Zhangjiakou), China (Hohhot), China (Ulanqab), China (Shenzhen), China (Heyuan), China (Guangzhou), China (Chengdu), and China (Hong Kong) 0.034
Japan (Tokyo), South Korea (Seoul), Singapore, Australia (Sydney), Malaysia (Kuala Lumpur), Indonesia (Jakarta), Philippines (Manila), Thailand (Bangkok), India (Mumbai), Germany (Frankfurt), UK (London), US (Silicon Valley), US (Virginia), and UAE (Dubai) 0.043

CU fees

You are charged CU fees for Internet NAT gateways on an hourly basis. Fees are calculated and bills are generated on an hourly basis. If you use an Internet NAT gateway for less than 1 hour, the usage duration is rounded up to 1 hour.

CU fee per hour = CU unit price (USD/CU) × Number of CUs consumed per hour
Number of CUs consumed per hour = Max(Number of CUs based on new connections per hour, Number of CUs based on concurrent connections per hour, Number of CUs based on data transfer per hour)

CUs measure the dimensions on which an Internet NAT gateway processes traffic. The following table describes the dimensions.

Metric Unit CU coefficient How the number of CUs per hour is calculated
Connections per second (CPS) Second 1,000 The system collects all CPS values within a billing cycle and then divides the highest CPS value by the CU coefficient to calculate the number of CUs. The number of CUs based on CPS is calculated by using the following formula:
Number of CUs based on CPS = Highest CPS value/CU coefficient
Concurrent connections (CONNS) Minute 10,000 The system collects all CONNS values within a billing cycle and then divides the highest CONNS value by the CU coefficient to calculate the number of CUs. The number of CUs based on CONNS is calculated by using the following formula:
Number of CUs based on CONNS = Highest CONNS value/CU coefficient
Data transfer (bytes) Hour 1 GB The system collects the total amount of data transfer including the inbound and outbound traffic within a billing cycle. Then, the system divides the total amount by the CU coefficient to calculate the number of CUs.
Note The amount of outbound and inbound network traffic collected by the system is equal to the amount of network traffic to be processed by a NAT gateway.
The number of CUs based on data transfer is calculated by using the following formula:
Number of CUs based on data transfer = Total amount of data transfer/CU coefficient
The following table lists the unit prices of CUs for Internet NAT gateways.
Note The prices listed in the following table are for reference only. The actual prices on the buy page shall prevail.
Region Unit price of CU(USD/CU/hour)
China (Hangzhou), China (Shanghai), China (Qingdao), China (Beijing), China (Zhangjiakou), China (Hohhot), China (Ulanqab), China (Shenzhen), China (Heyuan), China (Guangzhou), and China (Chengdu) 0.034
Japan (Tokyo), South Korea (Seoul), Singapore, Australia (Sydney), Malaysia (Kuala Lumpur), Indonesia (Jakarta), Philippines (Manila), Thailand (Bangkok), India (Mumbai), Germany (Frankfurt), UK (London), US (Silicon Valley), US (Virginia), and UAE (Dubai) 0.043

Billing example for CU fees

You created three VPC NAT gateways in the Germany (Frankfurt) region at 08:10:00 (UTC+8) on November 8, 2021. Then, you released them at 08:50:00 (UTC+8) on November 8, 2021. The following table describes the highest CPS value, the highest CONNS value, and the total amount of data transfer of the three VPC NAT gateways from 08:10:00 (UTC+8) to 08:50:00 (UTC+8).
Table 1. Highest metric values
Metric NAT Gateway 1 NAT Gateway 2 NAT Gateway 3
Highest CPS value (connections/second) 1100 32 0
Highest CONNS value (connections/minute) 20000 8 0
Total amount of data transfer (GB/hour) 3.5 0.0056 0
The following table describes the numbers of CUs based on new connections, concurrent connections, and data transfer, and the CU fees of the NAT gateways.
Table 2. Number of CUs and CU fees
Number of CUs NAT Gateway 1 NAT Gateway 2 NAT Gateway 3
Number of CUs based on CPS 1100÷1000=1.1 32÷1000=0.032 0
Number of CUs based on CONNS 20000÷10000=2 8÷10000=0.0008 0
Number of CUs based on data transfer 3.5÷1=3.5 0.0056÷1=0.0056 0
CU fee (USD) 3.5×0.043=0.1505 0.032×0.043=0.001376 0

Billing of related services

NAT gateways provide Internet-facing services by using elastic IP addresses (EIPs). You are charged for the EIPs that are associated with Internet NAT gateways. For more information, see Subscription and Pay-as-you-go.