The filter PIN is first set when you register the phone. The person who manages the device can set or change it later.
Steps
On a computer or another phone, go to my.kosherqinphone.com.
Choose Manage My Device.
Enter your phone’s serial number (Settings → About → Model & Hardware → Serial Number).
Choose Restrict my phone / edit your PIN.
Enter your new PIN and save.
Tips
If the phone is for a child, choose a code the child doesn’t know.
Once a PIN is set, you can also use it to lock things on the phone with Parental Controls. See “How do I use Parental Controls?”
Don’t know the current PIN? See “I forgot my filter PIN.”