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How to unlock your O2 iPhone

Posted on 27 Jul 2010 at 12:38

Paul Ockenden reveals why you don't have to jail-break your iPhone to escape O2

I've received quite a few emails from readers who own original O2-supplied iPhones that are now out of their contract term, asking about various ways to unlock these phones so they can be used on other mobile networks.

A couple of you noticed that the previous solution I recommended a while back – a SIM-shim called the Rebel Simcard – doesn’t work with iPhones running OS 3 or later, which is true and I probably should have mentioned it here before now. I still rate the Rebel Simcard as an unlocking solution for other phones, but up-to-date iPhone users will need to look elsewhere.

Another reader asked whether “jail-breaking” his phone would allow it to be used on other networks, and it’s certainly possible to jail-break just about any iPhone (although if you’re running OS version 3.1.3, it can be trickier).

Jail-breaking an iPhone doesn’t remove the network lock but merely loosens Apple’s grip on the device

However, contrary to what many people believe, jail-breaking an iPhone doesn’t remove the network lock but merely loosens Apple’s grip on the device, allowing you to install software that hasn’t received the Jobsial blessing. Oh, and it also lets you install an ever-increasing range of pirated and cracked software, which is the reason I’m not going to print any “how to jailbreak your phone” details in this column. If you really want to do that stuff, let Mr Google guide you.

However, if your phone has been jail-broken already then you can, in theory at least, install software that will remove the carrier lock from the device. The only problem is that – at the time of writing – all attempts to unlock an upgraded phone have failed. It doesn’t even help to downgrade the phone back to a previous OS version, because 3.1.3 also upgrades the “baseband”, which is essentially a mini-OS stored in firmware that looks after the GSM/GPRS/3G radio module.

The new baseband that 3.1.3 installs (called version 05.12.01) has so far proven difficult to unlock, and putting the phone back to 3.1.2 or earlier doesn’t restore the earlier radio code, so you’re stuck with the tightened-up version. A few people claim to have broken into this more secure baseband, but to date none of them have released a working unlock application.

Escaping O2

So what’s a poor iPhone user to do once their initial 18 or 24 months with O2 are up? For once the answer is very simple indeed: rather than waste time and effort trying to hack your phone with hardware or software, which can all-too-easily end by “bricking” the device, just ask O2 to unlock it for you!

That’s right, O2 will be happy to remove the lock from any iPhone it originally supplied. O2 even provides an unlocking web page to help you do this (although it isn’t publicised particularly well).

What you might find surprising is that this unlocking service is free, and O2 will even unlock iPhones that are still under contract, although it goes without saying that you’ll have to honour what remains of that contract. They’ll also unlock PAYG phones, although there’s a £15 charge for that.

I used this facility to unlock an iPhone 3G that Apple’s PR team gave me some time ago – I simply shoved an O2 SIM into it, loaded it up with £20 credit and then filled in the unlock form. Within a few days a message popped up on my phone saying that it was unlocked.

Actually, it wasn’t really unlocked – if you shove another network’s SIM in it you’ll get the dreaded “invalid SIM” message. What you need to do is, with this other SIM in the iPhone, connect to your PC or Mac and fire up iTunes. It will reboot itself and then it will recognise the SIM.

If that SIM comes from one of Apple’s official mobile network partners (O2, Vodafone and Orange in the UK), you should even find the APN correctly configured for network access. It’s a shame that more iPhone owners don’t realise that O2 offers this service, but perhaps this column will go some way towards remedying that.

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User comments

iPhone 4

I find it odd this article doesn't even mention the iPhone 4 even though I bet many users would be very interested in finding out if/how they can unlock their new iPhone 4 on O2.

Everything the article states is correct, I used this procedure to unlock my previous 3GS and it worked like a charm.

However, O2 still doesn't allow unlocking the new iPhone 4, stating quite vaguely "To make sure our iPhone 4 stock is reserved exclusively for genuine O2 customers during launch, we won't unlock iPhone 4 until after the launch period".

In fact, I just went to the Unlock page and submitted a request to unlock my iPhone 4 anyway, just to see what will happen. After I submitted the form, I simply got a "Form submitted successfully, we will get back to you within 14 days". So we shall see.

By vladman on 27 Jul 2010

iPhone 4

This article was written at the end of April, hence the lack of iPhone 4 coverage.

By PaulOckenden on 27 Jul 2010

Excellent article

Good to know for when my contract runs out, though by the time it does the conditions may have changed.

By mviracca on 27 Jul 2010


Thanks for the clarification Paul. Still, it was published on the 27th July, so I think my query was/is valid. Perhaps the article should include one line saying that iPhone 4 unlocking isn't yet possible.

By vladman on 29 Jul 2010

Thank you Paul

Thank you, although would have liked to know this was possible earlier, but never mind this is great, i travel to Russia a lot and use my phone there now, thank a lot.... and to the iphone 4 chap, i think O2 does reserve the right to get some money off us before we jump the wagon, D, but surelly soon they will do it... i got mine unlcoked within 24 hours...:)

By mobilegnet on 29 Jul 2010

Sadly I bought my iPhone 4 from the O2 store instead of the Apple store, and it wasn't unlocked :( What's even worse is that O2 aren't unlocking the iPhone 4 yet nor is there any free software out there!
I had to fork out some money to get mine unlocked from these guys, at least it doesn't lock up again after a firmware update because it's an official unlock through iTunes, not bad.

By timnash on 1 Aug 2010

Help with unlocking iphone 3g please

Hi. Thanks for the details in this article. I have a 3G iphone which is jailbroken, but I would like to unlock it properly and have tried your method, purchased an 02 sim, registered it, topped up £20 and then filled in the form. Got a text back saying it can't be unlocked. Phoned customer services who tell me the IMEI number of my phone is not corresponding to the 02 network. Any idea how I can get it to ? Do I need to unjailbreak it and update the software in order for this to happen? It is running 3.0.1 at the moment. Thanks for your help.

By Ellaroo on 13 Aug 2010

Help with unlocking iphone 3g please

Hi. Thanks for the details in this article. I have a 3G iphone which is jailbroken, but I would like to unlock it properly and have tried your method, purchased an 02 sim, registered it, topped up £20 and then filled in the form. Got a text back saying it can't be unlocked. Phoned customer services who tell me the IMEI number of my phone is not corresponding to the 02 network. Any idea how I can get it to ? Do I need to unjailbreak it and update the software in order for this to happen? It is running 3.0.1 at the moment. Thanks for your help.

By Ellaroo on 13 Aug 2010


As I said in the article, O2 will only unlock iPhones that were originally supplied by them. If yours was then you need to go back to them and complain.

By PaulOckenden on 13 Aug 2010

Thanks Paul

Hi Paul. Thanks for the reply. It originally did come from 02, as they were the only operators offering the iphone at the time. I purchased it from the CEX chain of stores though and CEX confirmed it is indeed an 02 phone when they look at the serial number. The customer services at 02 tell me it can sometimes take a few dats for a new IMEI number to be assocaited with the phone since putting in the new sim. In the meantime I have set it back to factory settings and am using the 02 sim in it. I will update when I get more news.

By Ellaroo on 13 Aug 2010

The IMEI doesn't change(*) - it was hard coded into the phone when it was manufactured, and inserting a new SIM doesn't change it.

(*) Actually, there ARE ways to change the IMEI of a phone, but it's illegal to do so in the UK.

By PaulOckenden on 13 Aug 2010


Hi. Got rejected to unlock twice, but finally, after a 3rd call to O2 at someone who knew what he was talking about he added my IMEI number to the system (it previously hadn't been picking it up) and requested an unlatch from the relevant department. Got a text this morning saying it was succesful and to fire up the new sim with itunes, and am very pleased to report it's working! Great article Paul, thank you! Just a note to others doing the same - make sure you use the new sim a bit as you need to specify 2 numbers that you call frequently on the unlock form and if you have any trouble request the unlatch like I did.

By Ellaroo on 15 Aug 2010

No need to have an O2 SIM or waste money!

I would like to say that while O2 will unlock your iPhone if purchased from them, you do not need an O2 SIM or indeed any SIM in the phone for the unlock! Do not waste any money topping up an O2 SIM if you don't need to. My 18 month O2 iPhone contract had expired, I moved to T Mobile and took my number with me. Anyway I then asked O2 to unlock my iPhone, there was no SIM in it at all, I just gave them my T Mobile number, the next day a message came through that my iPhone was unlocked so I put my T Mobile SIM in it, synced with iTunes, all done and no wasted credit!

By lasvegasno1 on 18 Sep 2010


Hi, great article. I did exactly this, i have a 3g iphone which i got on contract a long time ago. The contract is fully paid up and i have had two phones since, now have iphone4. I want to let my wife use my old 3g on ORANGE network using her Orange PAYG Sim. O2 told me this is fine, and unlocked my phone, or so they said. SIM not recognised and itunes tells me "the sim card inserted in this phone does not appear to be supported". Got back to O2. Unlocked "again". Same again. And again. 3 times now, they say they have unlocked it so it must be a phone fault. The phone is MINT, it is NOT the phone! Rang Apple and they confirmed phone still shows locked to O2. But O2 say they have unlocked it.

Does anyone know where on earth i go from here to use the phone i am supposed to OWN!?

By jerrrrrrry on 9 Oct 2010

Forgive me for sounding thick but if o2 unlock the phone, you put a new sim in and authenticate via itunes, what happens if you decide to use a different provider? Is the phone still locked to the new sim or is it free to move between sim providers? I want to sample networks before making a decision but don't want to be stuck with t-mobile (for example) if their coverage isn't good by me.

By darren10 on 27 Oct 2010

Hi. Looking for a second hand iphone 8gb 3g.

Will this method work if I buy an iphone originally supplied by 02? As a second owner?

By Spaceaware on 7 Nov 2010

I managed to do this without an O2 sim card. My mum bought a 2nd hand O2 iPhone4, it was pre-jailbroken. I didn't realise the jailbreak was to remove the network lock.

Anyway, long story short:

I visited the unlock page on the O2 website, then chatted online with a very helpful O2 man. Gave him my IMEI number and he unlocked the phone within 5 minutes. Once it was unlocked, I just had to connect it to iTunes.

By orvington on 19 Jan 2011

O2 locks all phones!

Thanks for the article, very useful.

After owning an Iphone for over a year, I discovered to my astonishment that it was locked to O2, EVEN though I bought it outright, and paid the full price for the phone, and I was assured by O2 at the time that the phone could be used on any network.

What they meant was, I was free to request to unlock the phone at any time. I now have to go through this procedure to get the full use of the phone I have bought.

Unlike the last poster, the O2 man was not very helpful, he did not see any issue with locking a phone I had paid for in full, and he did not fix it in 5 minutes. Rather he claimed that this was a procedure carried out by Apple and therefore takes two weeks.

So now I am sitting abroad, unable to use my phone locally for the next two weeks, and instead carrying a second phone for local calls.

My advice, even if you bought your phone on a PayGo deal from O2, try it with a different sim, and if it doesn't work, get it unlocked today!

(And please explain to O2 why this is not acceptable, and they should automatically unlock phones at the moment they are paid for in full...)

By ChrisS on 18 Feb 2011


I agree with jerrrrrrry. I've got PAYG and paid 15 pounds to get my phone unlocked. It received the text saying that the phone was 'unlatched' and that I should re-sync my phone. Did that, went to tmobile, and all I get is 'invalid sim' even when I try and syn with tmobiles sim. Tmobile assures me the sim is valid. They think the phone isn't truly unlocked. NOT a simple process and I have no faith that I'll ever see the light of day.

By bitspersecond on 10 Apr 2011


Immediately after writing the above, I called O2 to ask if my phone was truly 'unlatched' (aka unlocked). They couldn't tell me if it was or not, but they did agree to escalate another unlatch request. I got the text telling me it had been done and *this* time I powered the phone down, swapped sims, connected my iphone 3gs to my computer, powered it on and success! So, I actually did see this thru to the end. I now have a personal hotspot option available that wasn't there before.

By bitspersecond on 10 Apr 2011

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