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How to unlock your phone with a PUK code

If you have recently bought a locked phone, or your phone accidentally became locked, you’ll probably want to know how to unlock it. In order to do this, you’ll need to use a PUK code. But what exactly is it, and how do you get one?

Last updated: 3rd Sep 2020 at 12:04pm


Jump to how to get a PUK code by provider:


What is a locked phone?

Sometimes when you buy a new handset, it can be locked to the network you purchased it from. This means you can’t switch providers as the phone is only compatible with the one it is linked to. This is a common problem for people who buy phones on a contract, then decide to switch networks once the contract runs out.

Alternatively, you could have entered your PIN incorrectly too many times, causing the phone to lock as an anti-theft safety precaution. 

The easiest and most common way to unlock your phone is by using a PUK code. 


What is a PUK code?

A PUK code is a ‘Personal Unlocking Key’ (it is also sometimes referred to as a PUC code: ‘Personal Unlocking Code’). 

It is used to reset the PIN number on a phone if the protective software was triggered to lock the SIM card or handset. If the PIN/password is entered incorrectly more than three times, the phone locks itself. In order to unlock it, a PUK code is required. 

Though they are usually used by mobile providers to unlock a phone after its security measures have been triggered, a PUK code can also be used to  remove a network restriction from a phone. 

Be careful though: if you enter your PUK code incorrectly more than ten times, the SIM card will become irrecoverably blocked and you’ll require a new one. 


PUK versus PAC

A PAC code (‘Porting Authorisation Code’) is a sequence of numbers that you can request from your current provider in order to keep your number when switching networks. Keeping your number is convenient for contacts and online accounts. 

It is free to obtain a PAC code, though some networks may try to convince you not to leave before sending you your number. Once you have received your PAC code, you can send it to your new network so your number can be transferred over. 

Typically, you’ll need a PAC code after using a PUK code to allow you to switch networks and carry your number over


How do you get a PUK code?

If your locked phone is asking you for your PUK code, there’s a few ways that you can find it. 

Firstly, if you kept your SIM card package when it arrived, you can find the code on the back of the plastic you snapped your SIM card from. If you can’t find this or didn’t keep it, you can still contact your mobile network for a PUK code. 

Like obtaining a PAC code, the method varies between providers. 

EE, BT Mobile, Vodafone, O2, and Tesco Mobile are just some of the major networks that still sell locked phones. Though Ofcom plans to ban the selling of locked phones, for now, you will still need to contact these providers if you’ve bought a handset from them. 


Asda Mobile

If you have a phone with us, you can contact us for free on 0800 079 2723 to receive your PUK code to unlock your handset.  



To receive a PUK code from EE, you’ll need to log in to your EE account and follow these steps:

  • Menu > Manage device
  • Unblock SIM (Puk code)
  • Show PUK code

Once you have been given your PUK code, enter it into your phone and this will unlock the SIM. 


BT Mobile

Login to your BT Mobile account, and select the My phone and SIM button. You will find your PUK code listed under the information about your phone’s model and the SIM’s serial number. 



To obtain your PUK code from Vodafone, you’ll have to chat to a member of their team online and follow the steps they give you.



To find out what your PUK code is, you can enter your number on their website, or sign in to your O2 account and go to My device > Device details


Tesco Mobile

To retrieve your PUK code, you need to log in to your Tesco Mobile account. You will be able to find your PUK number under Personal Details


With all of these networks, you also have the option of calling them directly on each of their numbers to discuss receiving your PUK code. Of course, you would probably have to use someone else’s phone if yours is locked. We have a variety of locked and unlocked handsets available to purchase from our online store or in some of our shops. 


We hope you’ve found our guide to PUK codes useful. Now that your phone is unlocked, you’re free to switch to whichever network you fancy. Not that we’re biased, but you should consider the many benefits that come with joining Asda Mobile! 


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