Check your phone settings for carrier lock or network lock status
Remove the SIM card and insert a SIM from another carrier
Make a test call, send a text, or use mobile data with the new SIM
Contact your current carrier and ask if the phone is unlocked
Use your phone’s IMEI on the carrier’s unlock status checker
Restart the phone after inserting a different carrier’s SIM
If the phone works on another carrier’s network, it is unlocked