'3' Sim will not work with unlocked phones?


Standard Member
Dear All,

I have the K800i and my contract is due to run for another 10 months. I have tried my sim in several unlocked phones, but it never works, can I do anything that will allow me to change phones using my current sim please?




Active Member
Does it work in your 3 phone? I use my 3 SIM in an unlocked phone with no problems. Have tried it with other phones and it works fine as well. Get the guys at the 3 shop to check it out for you cause it should work in any phone that is not network locked.


Standard Member
Yes it works in my 3 phone...but to date has not worked in other unlocked phones. However that might be because they were not 3G phones, if that makes a difference?



Active Member
Hi, bit of a story to this one.

The actual sims are no different to voda,o2,t-mobile and orange.

The difference is that 3 use a backup network for when you have no 3G signal (o2 if purchased before 2007 and orange if purchased in 2007 onwards). Because of this they want you using 3G as much as possible because they have to pay if you are in a poor signal area. This was in theory a good idea because it meant it cost the company more to give you crap service! In the early days they only allowed IMEI's (phone serial numbers) on the network that were "3" branded.

When the other networks started using 3G they (unofficially) changed the rules to allow non "3" 3G phones, this was as I say unofficial and simply done to reduce call centre calls about how to get unsupported phones to work. However if you were not using 3G enough (i.e disabled 3g on the menu (symbian phones) or live in a poor signal area)) then your account will be marked and your phone will only work with a "3" phone. This is because they want to make sure you are actually in a bad signal area and not just switching to 2G to get better battery life / signal.

As I said, this is all done unofficially. Because of this your contract will state that you must use the equipment provided by them.


Standard Member
dont forget that a 3 sim card is a utms sim and not grps so as stated will not work in non 3g phones. my wife can use her payg sim in any of her old three phones.

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