Many of the mobile complaints (28.2 per cent) had to do with network coverage, including reduced or no reception, poor voice quality and dropped calls, the TIO said. However, the number of those complaints (25,770) was 13.5 per cent less than 2011-12.
The TIO said billing and payment issues, customer service complaints and overall fault concerns all reduced in the financial year.
However, Cohen said telcos can still improve their handling of customer complaints. He said more than half of the complaints to the TIO were about customer service issues and most were resolved through referrals to senior complaint handlers of the service providers.
"There are still too many complaints that consumers are unable to resolve with their telcos, and there remain many opportunities for telcos to serve their customers better so that they don't need to come to the TIO."
The Australian Communications Consumer Action Network (ACCAN), which earlier this month called the TIO the "busiest ombudsman" in Australia, agreed that it's not time for telcos to declare victory.
"Complaint figures are starting to go from the stratosphere back down to Earth but there is still significant room for improvement," said ACCAN CEO Teresa Corbin.
"This significant drop in TIO complaints shows that enhanced consumer protections introduced with the TCP Code and a new focus on fixing customer service issues by industry is beginning to have the desired effect."
"But it's important to keep some perspective--the 158,652 new complaints are coming off record highs and are still considerably higher than the number of complaints dealt with by the financial ombudsman, which includes the banks."
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