One in five (20 percent) Brits that use a mobile phone to browse the web are unaware there is a limit of the amount of data they can use, says Thinkbroadband.com.

Research by the broadband comparison site revealed 58 percent of mobile phone users prefer to access the web from a handset which could leave many that are unaware of their download limits with high bills. Furthermore, 43 percent admit they never check their bill to see if they have been charged for excess data use.

"The results of this survey highlight why, since the rise in popularity of smartphones over the past couple of years, many Brits are experiencing financial headaches over their mobile phone bills," said Sebastien Lahtinen, co-founder of Thinkbroadband.com.

"It is important to make sure you have a data bundle to suit your needs. Providers can offer a number of different packages to coincide with the amount of internet you will be using. Most of all it is important to monitor your bills each month to ensure you are not paying over the odds for the amount of data you are using."