Showing results for 
Search instead for 
Did you mean: 

How to set up a SIM pin on O2

Level 94: Supreme
  • 86960 Posts
  • 594 Topics
  • 5120 Solutions

Everyone should set up a sim pin lock on their phone, more so if you have a contract phone. Combined with a screen lock it's the best security against unauthorised usage should the phone be lost/stolen or left unattended.



  • Go to settings and tap on phone settings.
  • Scroll to the bottom and tap on sim pin.
  • Slide the toggle to ON.
  • Enter the O2 default pin 0000
  • Tap change pin.
  • Enter the default pin again 0000
  • Enter a 4 digit pin you can remember, preferably not your birthday.
  • Re-enter your chosen pin and it should then be set up. As well as safeguarding your phone it will also prevent the sim being used in a different phone.
  • Bear in mind that entering the sim pin incorrectly 3 times will block the sim. If this happens you will need the PUK (Pin Unblocking Key). This can be found in My O2 or by calling customer service or using Web chat.
  • Entering the PUK incorrectly 10 times will permanently block the sim card and a new one will be required.



  • Very similar set up to iphone, again all you need is the default pin 0000
  • Go to Menu and Settings.
  • Security/Set up sim card lock.
  • Tick Lock sim card.
  • You need to enter 0000 then a new 4 digit pin which you will be asked to confirm.
  • The exact same conditions of 3 attempts then PUK  also apply to Android or Windows etc.
  • Combine this with a screen lock and a security app such as Lookout, Avast or similar and you have done as much as you can to prevent unauthorised use of your simcard .