Existing designated monthly service plan customers can subscribe One-Card-Two-Numbers service at retail stores. If you have already set credit card autopay as the payment method, you can also log in the online shop account to subscribe One-Card-Two-Numbers service; New customers can subscribe One-Card-Two-Numbers service directly when applying for a designated monthly service plan at retail stores or through online shop (if through the online shop, credit card autopay must be set as the payment method). When subscribing One-Card-Two-Numbers service, customers need to submit the Real-name registration information of the Chinese Mainland number. Once the Real-name registration information is manually verified, the Chinese Mainland number will be activated.

The standard fee for Chinese Mainland number is HK$10 per month. Subscribing One-Card-Two-Numbers service together when signing up for the designated monthly service plan at retail stores or via online shop, the monthly fee of Chinese Mainland number can be waived during the contract period. Customers can receive calls from Chinese Mainland or make calls to Chinese Mainland using Chinese Mainland number in Hong Kong. The charge for the above business scenarios varies depending on the monthly service plan. Please refer to the corresponding subscribing page for more details.

The Chinese mainland government has now implemented the "Regulations on the Registration of Real Identity Information for Telephone Users" (referred to as the "above-mentioned registration"). Customers who want to use (or continue using) a mobile number in mainland China must successfully complete the above-mentioned registration as required by the Chinese mainland authorities and comply with other laws, regulations, and rules in mainland China. The Chinese mainland authorities have the final authority to review the above-mentioned registration, and China Unicom Hong Kong does not guarantee the success of the registration.

To comply with the “Regulations on the Registration of Real Identity Information for Telephone Users”, the SIM card owner is required to fill in, submit the relevant personal information for manual review via retail stores or online shop and complete the Real-name registration of the Chinese Mainland number.

Each Hong Kong number can only apply for a maximum of 1 Mainland China number as a supplementary number. This does not apply to the free-contract service of the " CUniq GO Monthly " and " CUniq GO Daily," or other prepaid card services. A maximum of five Chinese Mainland numbers can be registered for each ID number of the same type of identification document (All Chinese Mainland numbers belonging to China United Network Communications Group Co., Ltd. (referred to as "China Unicom") are counted together). Below types of ID documents are accepted for Chinese Mainland number Real-Name registration: Mainland Travel Permit for Hong Kong and Macao Residents/ Resident Identity Card of the People's Republic of China / Mainland Travel Permit for Taiwan Residents.