Mobile broadband subscribers are being urged to keep a closer eye on their download caps after Broadband Expert revealed users could face up to a £200 bill if they exceed their limit by 1GB.

Research by the broadband comparison site revealed that O2 and 3 charge the most for exceeding download limits, with O2 expecting customers to fork out at 19.6p per MB. 3 charges users 10p per MB.

Vodafone charges £15 per GB (equivalent of 1.46p per Mb) and Orange charges 1.46p per Mb. T-Mobile is the only mobile broadband provider that doesn't charge for exceeding download limits.

"Information on run on rates is not always easy to find and not obviously visible on most advertising," said Rob Webber, Broadband Expert's commercial director.

Webber was keen to point out that the exception to this is O2, which clearly communicates the rates on its website.

"Whilst many deals may appear to be very closely matched, it is important to take excess charges into account, as there can be huge differences between one provider and another," added Webber.

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