
First of all, if you want to continue to use your cell phone number during your trip, you need to make sure that your cell phone number is enabled for “international roaming” service before you leave, and find out the roaming rate, which is usually much more expensive than the local service charge.
If you are not sure if your phone card will work in China, it is highly recommended to check with your phone carrier before you leave, as some foreign carriers do not have cooperation agreements with Chinese carriers.
Secondly, if you are not on such a short-term business trip of 2-3 days, it is recommended that you can buy a physical SIM card for mainland China, with cheap rates, stable service and very convenient handling, with two ways of purchase: