People walk past a Telstra logo in Sydney on February 12, 2015. (WILLIAM WEST/AFP/Getty Images)

Complaints against Australian telecommunications providers have risen in the latest ombudsman’s report, with Telstra and Optus tied for the title of most complained-about company.

The Telecommunications Industry Ombudsman on Wednesday released numbers for the quarter ending March 31, which showed the entire industry recording 8.4 complaints per 10,000 services-in-operation. This was up 31% from the prior period, when 6.4 complaints were recorded.

Telstra and Optus both had 9.3 complaints recorded against them to “top” the table, which a Telstra spokesperson blamed on the NBN.

“The data shows that a significant volume of TIO complaints are for customer experiences relating to NBN. There are challenges here for the broader industry,” the spokesperson said.

“We are working with NBNco where we believe changes can help improve the NBN experience.”

The spokesperson added that Telstra is “moving a significant number of customers to the NBN every month” and that the company has “a number of initiatives” under way to reduce overall complaints.

Business Insider has contacted Optus for comment.

Meanwhile Vodafone was celebrating the latest stats as a victory, with it bucking the overall industry trend by reducing the number of complaints to the ombudsman to 3.9 per 10,000 services, compared to 5.0 for the previous quarter.

Complaints to the TIO per 10,000 services. (Source: TIO)

“A 22% decline in the rate of complaints between the December and March quarters suggests to us that we’ve continued to improve the service we offer, and we’re very pleased we’ve been able to do even better for our customers,” a Vodafone Australia spokesperson said.

The spokesperson attributed Vodafone’s latest complaints rate, which was at less than half the industry average, to “strong network performance”, avoidance of bill shock and “commitment to customer service”.

But if Telstra is correct in attributing a rise in complaints to the NBN, Vodafone’s happy days may not last long. Vodafone Australia flagged this month that it would enter the NBN retail market “later this year” and called for customers to register their interest.

Independent telcos Amaysim and Pivotel again put up a good fight against their bigger rivals, recording just 0.9 and 1.3 complaints per 10,000 services.

The ombudsman has reported complaint rates for each company since the September 2013 quarter. Optus had topped the table for consecutive quarters in recent years before Telstra took the crown for December 2016.

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