Mobile phones can be bought locked to a specific Mobile Phone Network, or unlocked. Unlocking Mobile Phones

But just what does this mean, and what are the advantages and disadvantages of either.

If you have a phone that is locked to a Mobile Network are you "locked" forever ?

In this article we explore the procedures, advantages and disadvantages of unlocking mobile phones.

What is Mobile Phone Locking ?

When you enter into a contract for a fixed term it is typical for the Network to make the contract more attractive by offering special rates for calls and / or text messaging.

For example 300 free minutes plus 100 free texts per month for £20.00p per month.

Or, 500 free minutes plus 175 free texts per month for £27.50p per month.

Actually, between you and me, do we really think they are "free"?

Not really. The network is charging you a fixed fee - the call, and text, costs are covered by the monthly fee.

A portion of the fee gets allocated to "free" calls and texts.

To make the deal even more attractive the network probably includes a free telephone.

Again - do we really believe it to be "free"?

The monthly contract fee also covers the cost of the phone - if not, then I ask why it is that the more versatile the phone the dearer the monthly fee ?

A basic phone, 300 free call minutes and 100 free texts per month for £32.50p per month.

Or a telephone with emailing . . .

Better still, one that allows you to email, and surf the world wide web . . .£35.00p per month.

Or even all the above, plus loading on your favourite music downloads . . . £40.00p per month.

A bit like a 20 year old mini costing you less than the latest top of the range "must have" "anyone who is anyone has got one".

OK, I think you will get the idea now!

To recoup the cost of the telephone, and services that it provides, there is a minimum contract term - balancing the value of the phone and the monthly fee, the network determines how long it will take them to recoup the value of the "freebies".

Therefore, to recoup the cost of the freebies, the network will tie you in for a minimum fixed term - this is done by "locking" the SIM and phone to the network.

If you want to get out of the contract the network will, typically, charge you the remaining months on the contract, plus any other contractual fees that are probably in the contract that you agreed to at the time of making the contract - if they even allow you to get out.

Getting out is referred to as unlocking.

How do I know if my mobile phone handset is Locked ?

Knowing if your handset is locked to a specific network can be quite a simple process.

Firstly, if you are, or have recently been, in a contract your written contract should give a start date and a term duration in months or a specific end date.

If you are within the start date and the number of months duration, then you are most likely locked in, unless you have negotiated a "get out" settlement.

If you are currently looking at buying a handset it would be prudent to ask the seller if the handset is locked, and maybe have written statement to this effect.

Alternatively, remove the SIM card that is in your phone handset and insert a SIM card that is for a different Network.

When the alternative network SIM card is inserted, turn on your handset.

During, or just after, powering on your handset you might have a message displayed on your handset screen.

If you get a message which reads something along the lines of any of the following:

  • Insert Correct SIM Card;
  • Enter Special Code;
  • Enter Unlock Code;
  • Enter Restriction Code;
  • Enter Network Code;
  • SIM Not Valid;
  • SIM rejected.

. . . the handset you have could well be Locked to a specific Network.

How do I get my SIM card, or mobile phone phone unlocked ?

This process is quite simple.

There are some things that you need to be aware of before attempting to unlock your phone:

- The phone may have to be a pre-paid phone;
- The network have to have recovered any subsidy;
- The phone may have to be over 12 months old;
- Unlocking your handset may invalidate your handset warranty;
- Handset software upgrades and/or updates may no longer be available to download.

You might need to give your existing network one months notice - this can be clarified when you call your network.

Simply call your existing network provider and tell them that you wish to unlock your mobile phone.

Before calling you will typically require the following information to hand:

- Your mobile phone number;
- The network (and country) that your phone is locked to;
- Phone manufacturer;
- Phone model number;
- Phone IMEI (International Mobile Equipment Identity) number.

- If you wish to keep (transfer) your existing phone number you will need your PAC (Porting Authorisation Code) from your existing Network Provider in advance of transferring - you would be advised to check with your proposed new Network Provider if you need a PAC before creating an account with them and keep your phone number.

Your phone IMEI number is usually a 15 digit number. This can be obtained by calling (from your mobile phone) the following number: *#06# (star hash zero six hash) - your phone IMEI number will then be displayed on your phone screen.

Unlocking your mobile phone does not mean you have to transfer your existing phone number - often you have a choice of transferring your existing phone number or being issued with a new phone number.

For more information on IMEI you might like to read our article, specifically on IMEI, titled IMEI And Phone Identity.

Also, if you are planning to transfer your phone number to a different Network PIN PAC PUK and mobile phones useful, particularly the article section explaining PAC.

When you get your PAC number, sometimes also called a NUC (Network Unlocking Code) from your existing Network your PAC (or NUC) will typically be valid for 30 calendar days.

Mobile Number Portability, often referred to as MNP, allows mobile phones users to keep their existing phone number when the user transfers from one network to a different network.


If you feel more confident in getting your phone unlocked by another person, there are a number of Mobile Phone Unlocking Service providers available who can offer further advice and unlock your mobile phone for you.

This will most likely involve taking your mobile phone into the provider's premises.

The service provider may make a nominal charge for providing this service.

We have three videos relating to the unlocking mobile phone handsets which you might like to watch.

Mobile Phone Unlocking - What Is It ?

Unlocking the Monte Carlo Skate ZTE.

Unlocking the San Fransisco ZTE Blade.

Does SIMsurprise Offer A Mobile Phone Unlocking Service ?

At this stage, unfortunately SIMsurprise does not offer a mobile phone unlocking service.

This article can be used on your own website, free of charge, providing this article is unaltered and the information and link in the box below is also included with the article.

Tim Austin writes articles about various aspects of the Mobile Phone industry.

More articles are available by visiting

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