The cost of unlocking your iPhone 4…

If you love your iPhone and you love to travel you definitely won’t love the way carriers lock the iPhone onto their network. This prevents you from using a pre-paid local SIM card once you arrive at your destination which can save a fortune on phone calls and SMS messages.

So what’s the story with the iPhone 4? We polled Telstra Vodafone 3 and Optus on their iPhone 4 unlocking policy.

If you buy an iPhone 4 outright from Apple it comes unlocked of course. That’s just as it should be. You’ve paid anywhere from $859 to $999 for the phone. It’s yours.

All Telstra iPhone 4 units will be locked to Next G with a flat $150 fee to unlock them.

An Optus spokesman confirmed that while their iPhone 4 handsets would be locked “if you want to unlock the iPhone there is no extra charge.”

Vodafone and 3 will sell the iPhone 4 locked but a spokesperson confirmed to APC that both carriers “will unlock the handset free of charge for postpaid (contracted) iPhone 4 customers”.

This is a significant but very welcome change from Vodafone’s previous policy under which the iPhone 3G and 3GS would be unlocked for between $75-$100 if you were in the first six months of your contract and between $25-$50 after that period.