Operators could be doing more to help consumers understand the costs associated with data usage on mobiles, according to the independent organisation Ombudsman Services.
"There are three things operators need to do. First of all, be very clear on what they mean by unlimited in the advertisements," chief ombudsman Lewis Shand Smith told the BBC. "Secondly, give advice to consumers in the UK just as they do when people are roaming abroad, and thirdly, give advice on the amount of data that is being downloaded."
The only UK operator to offer an "unlimited" data package that is not subject to a fair usage policy (FUP) is Three. Customers on non-unlimited data plans, at Three and other networks, are usually given a certain number of megabytes' usage per month and charged extra if it is exceeded.
Ombudsman Services conceded that while it does not see a high number of complaints, data-related 'bill shock' is a growing problem due to the proliferation of smartphones and high-data usage services such as streaming or downloading music or TV content.
"We see it as an emerging issue. We have begun to see an increasing number of complaints about this and when they happen they can have a considerable impact on the consumer," a spokesman for the service told ZDNet UK. "It is part of the value of having an ombudsman service that we can raise awareness of problems like this before they become too large."
The consumer who roams in Europe is treated better than the mobile phone user in the UK.– Lewis Shand Smith, communications ombudsman
The ombudsman also called for more parity between international and domestic roaming.
"The consumer who roams in Europe is treated better than the mobile phone user in the UK. Simply because when we roam in Europe the network is required to tell us when we're approaching our download limit, but there is no such requirement for us when we use our phones to download in the UK," the spokesman said.
In March 2010, European rules were put into place that meant that mobile operators must advise roaming users within the EU when they're approaching a limit of €50 (£43) and must stop mobile data services when they reach it.
As well as telling operators that there are steps they need to take to make the cost of data usage within the UK more transparent, the ombudsman also said that consumers need to make more of an effort to understand the terms and conditions of the package they are signing up to for fixed periods.
"If a welcome letter, which clearly explains the limit, isn't read or is ignored, there is nothing we can do to help. Where the information provided by the company is missing, insufficient or misleading, the ombudsman can get involved," Ombudsman Services said in its statement.
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