Insert the SIM into a phone
Turn on the phone
Open the Phone or Dialer app
Dial the carrier’s USSD code for your number, if available
Check the SIM card settings in the phone menu
Go to Settings
Tap About phone or About device
Tap Status or SIM status
Look for My phone number or SIM number
Check the Contacts app for your own contact card
Send a text or call another phone and read the displayed number
Log in to your carrier account or app
Check the number printed on the SIM card packaging
Contact your mobile carrier and ask for the number linked to the SIM