Bill Shock is the term used when a customer is faced with very high unexpected charges on their mobile phone bill. This usually occurs when data is largely overused without a suited data plan or when customers are not fully aware of roaming charges when using their phones internationally.
The Federal Communications Commission (FCC) in the United States conducted a survey in which results revealed that 17 percent of those who responded experienced sudden increases in their bill even though they hadn't changed their data plans.
CTIA, the trade association that represents mobile phone carries, questioned this survey and insisted that customers are well informed about their calls and data plans and that there is no need for a further mandate of regulation.
A U.S. senator, Tim Udall introduced an act in September 2010 called the "Cell Phone Bill Shock Act" in response to the research. It would require mobile carriers to notify customers when they have reached 80 percent of their monthly minutes limit and to obtain consent before charging for services outside of their monthly plan.
Since July 2010 in Europe, Eurotarriff has protected customers from Bill Shock by introducing a cut-off point once a phone bill reaches 50 euro unless the customer has chosen another cut-off limit.