Comparison website WhistleOut has launched an independent analysis of Australian mobile cap plans, revealing that hidden mobile phone costs are confusing and misleading to consumers.

Director of WhistleOut, Cameron Craig, said the findings make a good argument for industry reform.

"Unlike the USA and UK, consumers in Australia would actually need to use a mathematical formula if they really want understand any of the marketing language used by the telcos in Australia," Craig said.

"They'd need take the advertised value of, say, $500 of calls per month, and then divide this by flagfall costs, per minute pricing and other charges."

Craig said WhistleOut's findings back up claims made from the Australian Communication and Media Authority (ACMA) that telco consumers because of the constant bill shock they receive each month.