How to calculate the monthly rental fee for China Mobile’s primary and secondary cards?

For multi-account business, each secondary account is 5 yuan/month, which is uniformly charged by the main account, and the deduction rule is immediate deduction. The charges for calls, short messages and multimedia messages generated during the use of the secondary number will be paid by the primary number according to its current tariff standards (except for external SMS sent by the physical secondary number), and the secondary number will not be billed separately. The secondary number only supports calls, text messages, and MMS reception functions. The processing procedures are different in different provinces, cities and regions. Please refer to 10086 real-time consultation for details.