What is the difference between pre-pay phones and unlocked/sim free phones?

2 posts

Hi,
I have been looking at mobile phones recently and i notices that there were two options:
- Pre-pay mobile phones
- Sim free/unlocked mobile phones

The Sim free/ unlocked phones were also significantly more expensive than the pre-pay phones and as i am considering buying a new phone i would like to know what the difference is between the two.

Will be grateful for any help,
Mike