For MTN
Your default PIN is 0000.
To change your pin:
Dial: *321*Default Pin*New Pin*New Pin#
Example: *321*0000*1234*1234#
For 9mobile
Your default PIN is 0000.
To change your pin:
Dial: *247*Default Pin*New Pin# or *247*Old Pin*New Pin#
Example: *247*0000*1234#
For GLO
Your default PIN is 00000.
To change your pin:
Dial: *131*Default Pin*New Pin*New Pin#
Example: *131*0000*12345*12345#
For AIRTEL
Your default PIN is 1234.
To change your pin:
Dial *321#
select option 3 “PIN management” and follow the prompts.