lots of phones are still network locked.
most (if not all I think) PAYG phones are network locked by default. so you have to pay to unlock them.
also iphones unless bought from apple lock to the first sim inserted into them. to use on another network you have to ask the network provider to unlock.
the cost of unlocking (and whether they will) depends on carrier.
For example, o2 unlock an iphone for free after 12 months of the contract using a webform. others make you pay regardless of your contract being done
giffgaff have a handy page for this shizzle here
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however a simple test is put in another sim (order a freebie one from somewhere like quidoc or the carrier you want) and give it a go so you know if it needs unlocking
Posted By: doncoop, Aug 14, 16:50:08
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