Do you need to unlock your mobile phone before you can buy a prepaid card in Thailand?

I'm a T-Mobile phone user and will be going to Thailand for a few months. When I'm in Bangkok, I want to buy a prepaid phone card.





Does anyone know if you you need to unlock your mobile phone before you can buy a prepaid card in Thailand? If your phone is unlocked, then, when you are back in the UK, is there any problem with your current network?

Do you need to unlock your mobile phone before you can buy a prepaid card in Thailand?
Yes you need to unlock it with triple zero of ask the T Mobile company in Thailand, they would help you. There should not be a problem using in UK after using it in Thailand.
Reply:Most likely you won't and if you do wait until you are there to unlock it. Far cheaper. It will cost you about £1 to have it unlocked. There are many places that will do it. Try at Pantip Plaza if you need it unlocked or the mobile phone section at MBK shopping mall.





I used an AIS One2call. I paid around 300baht (£5) and it came with 100baht free call allowance.





After posting I just read the answer above.





I have used an AIS One2call sim card in both an O2 %26amp; Orange phones. Both were Nokia and neither needing unlocking.
Reply:yes but they can do it with cable