How do Unicom users inquire about international roaming charges before going abroad?

Before going abroad, you need to confirm whether China Unicom has launched GSM/WCDMA/LET international roaming service with the operator of the country or region you are going to. You can get the latest information about China Unicom's international roaming access countries or regions, international roaming services and international roaming charges through China Unicom APP, China Unicom's online business hall and China Unicom business hall, or you can call China Unicom's customer service phone number 10 10.