High mobile phone bills and dodgy coverage were behind a nine per cent rise in mobile complaints to the telco watchdog, with one user hit with a $12,500 bill.
The Telecommunications Industry Ombudsman (TIO) annual report found thousands of frustrated consumers are unable to resolve simple disputes with their phone companies, while problems with mobiles are the biggest gripe.
The 2011/12 report, released on Monday, cites the case of one man who was hit with a whopping $12,500 bill due to global roaming charges.
The man managed to beat the bill thanks to the ombudsman organising conciliation talks.
The overall number of complaints to the TIO fell by two per cent to 193,702, but concerns about mobile phones made up two-thirds of that at 122,834.
"This year we have seen far too often, in literally tens of thousands of cases, consumers come to us frustrated, exhausted and emotional after being unable to resolve often very simple complaints with their service providers," ombudsman Simon Cohen told reporters in Melbourne.
Mr Cohen said the TIO used conciliation between customers and telcos to handle about 10 per cent of the overall complaints after referral to complaint-handling specialists at telco companies failed to fix disputes.
Such conciliation achieved a 90 per cent customer satisfaction rate, the report says.
Mobile users' complaints about "financial over-commitment" doubled to 15,752 in 2011/12, with many customers blaming their telcos for not providing adequate tools to control their spending.
A case study said a man, Shane, contacted the ombudsman after his telco told him he was liable for $12,500 in roaming charges upon his return to Australia from an overseas trip.
Shane argued he had taken reasonable precautions by arranging a roaming plan - which proved to be a poorly-recommended plan by the company for his circumstances - before his trip.
The watchdog's conciliation efforts resulted in the company initially offering to reduce the debt by 75 per cent, then 90 per cent, before it later waived the entire bill.
The big three telcos - Telstra, Optus and Vodafone - accounted for 61,991, 41,602 and 39,588 complaints respectively, the report found.
Complaints about Telstra plummeted 21 per cent, but gripes with Optus and Vodafone jumped 47 and 11 per cent respectively.
This reflected Telstra's improved customer service efforts, contrasted with a raft of faults, poor expense tracking and disputed internet charge issues with Optus and Vodafone, Mr Cohen said.
Mr Cohen said the rising number of concerns about mobiles reflects an increased usage of smartphones, and highlights the importance of new spend-management rules to be imposed on carriers from 2013 through the new Telecommunications Consumer Protection Code.
That overall complaints have dipped positively reflects efforts by a number of telcos to improve their customer service, he says.