Overall, the figure (167,831) rose for the year and despite a downward trend in the last quarter, Labor said the overall number still remained far too high.
Labor Shadow Communications Minister Michelle Rowland welcomed the shift in trend but underlined the fact that there was still a great deal to be done.
“Consumer interactions remain too complex and poor customer service continues to leave many in the community wondering where the buck stops," she said.
Shadow Regional Communications Minister Stephen Jones said the number of complaints fielded by the TIO was more than four times that made to the Financial Services Ombudsman.
“Clearly consumers and small business expect improvements," he said.
Rowland and Jones said small businesses should have more protection to ensure that problems were fixed. "
"This is why Labor has announced it will establish an NBN Service Guarantee, building on recent steps by the ACCC, to improve accountability and better safeguard consumers and small businesses from poor outcomes such as excessive downtime," they said.
The Australian Communications Consumer Action Network said it was frustrating to see that complaints had again increased for the year.
ACCAN, which is the peak body representing consumers, said it was "concerned that 167,831 residential and small business consumers have had significant enough issues with their retail service provider that they have felt the need to reach out to the TIO to mediate the process".
“We’ve seen a 6.2% increase in complaints to the TIO from the previous financial year. Although the last quarter has shown improvement, this is the third year in a row that the complaint numbers have climbed. It is time to draw a line in the sand – consumers deserve better from their telco providers,” said ACCAN chief executive Teresa Corbin.
ACCAN said it was encouraging to see some telcos had a reduction in complaints. But it was disappointed to note that Optus Group and newcomer MyRepublic had a significant increase in complaints, with the latter facing an astronomical 101.6% growth year-on-year.
My Republic contested this figure, with its managing director Nicholas Demos saying: "MyRepublic is a relative newcomer, only launching in late 2016, which is why it did not register full data for the previous year.
"Therefore, while the figure for the total number of complaints in the most recent financial year is correct, it is impossible to calculate a year-on-year shift without having been in full operation for the previous year."
However, ACCAN pointed out that this was a marked improvement on last year, when nine of the top 10 providers saw double-digit increases in complaint numbers.
“Customer service continues to be an ongoing issue for Australia’s telco providers. On behalf of Australian telco customers, we will continue to work with the industry and regulators to push for better outcomes such as reduced timeframes to resolve issues and increased first contact resolution,” Corbin said.
Reacting to the TIO report, John Stanton, chief executive of the industry lobby group Communications Alliance, said the statistics demonstrated that "recent industry, government and regulatory initiatives are improving outcomes for individual and small business telco consumers".
“Recent industry, government and regulatory improvements are starting to deliver a dividend for consumers," he said. "These measures, which are either the initiative of, or supported by, industry, demonstrate how seriously telcos are taking the need to improve consumer outcomes and drive down complaint numbers.
“These positive results continue to demonstrate the efficacy of co-regulation. The ability to respond agilely to changing technologies and market conditions, such as through Communications Alliance’s publication of key codes and guidelines to assist with NBN migration, initiatives by individual service providers and NBN Co, in combination with recent policy and regulatory changes provides better outcomes for consumers.
“The strengthening of the enforceable Telecommunications Consumer Protections Code — which is currently underway — will continue to improve service provision for telecommunications consumers.
“We expect that the Communications Alliance’s upcoming Complaints in Context Report will shed further light on the performance of the industry."