A Dell Mini 3 can be unlocked with an unlock code. The Dell Mini 3 unlocked mobile phone should work on any GSM carrier or network. You will need an unlock code in order to remove the SIM lock that comes on most SIM based cell phones by default. If your Dell Mini 3 has a SIM lock on it, then it will prevent you from using the mobile phone with any other carriers.
I would first recommend you try getting a Dell Mini 3 unlock code by calling up your current phone carrier. In exchange, they will need your Dell Mini 3′s IMEI number. Your IMEI number is unique to your mobile device and the Dell unlock code will be calculated using it. You can get the IMEI number on your Dell Mini 3 simply by typing *#06# and hitting the enter or send button. If you do not currently have a carrier or cannot get a free unlock code, then I would reccomend trying some of the unlock code websites that I have reviewed below.
Once you have your unlock code, you can begin the Dell Mini 3 unlocking steps below.
How To Unlock A Dell Mini 3 (SIM Unlock)
1. Power on your Dell mobile phone with an unaccepted SIM card.
2. Enter your Dell unlock code you attained earlier.
3. Your Dell mobile phone should now be unlocked and may automatically reboot.