What is a SIM network unlock PIN?
A SIM network unlock PIN is a numerical code that is used to unlock your handset so you can use any network. The code can go by many other names and is commonly referred to as an ‘unlock code’.
Alternative names for a SIM network unlock PIN include:
- NUC (network unlock code)
- NCK (network control key)
- NUP (network unlock pin)
- Unlock code
- Network lock control key
You should not confuse it with a SIM unlock PIN which is used to lock / unlock the SIM card of your handset.
Why do you need a SIM network unlock PIN?
Mobile networks such as EE, O2 or Vodafone along with manufacturers such as Huawei and Samsung insist this is the best method of protecting both the phone and their contracts. In most instances you have only 3 attempts to enter a correct SIM network unlock PIN.
Most notably, if you enter the wrong unlock code more than 3 times you will get a PUK (personal unblocking key) request screen. Having these security measures in place allows the mobile networks greater control over the handset once it has be purchased.
Consequently, if you have purchased a second-hand mobile it becomes increasing difficult to unlock it to use another network.