The number of consumers unhappy about being hooked up to the national broadband network has surged, with complaints about unusable NBN landline and internet services jumping more than 40 percent in the last three months of 2015.
The Telecommunications Industry Ombudsman (TIO) said on Friday there were 210 complaints about unusable NBN landlines in the three months to December, a 48 percent increase on the previous quarter.
Complaints about unusable internet services hit 184 over the same period, up 42.6 percent from the previous corresponding period.
The TIO said most unusable services complaints related to "difficulties occurring either during migration to the NBN, or during the first few weeks of services being activated on the NBN".
"Some consumer complaints related to both unusable landline and unusable internet issues," the TIO said.
It said some services stopped working during the transition from the copper network to the NBN while others shut down after several weeks.
It said there were also cases where NBN services stopped "when a battery back-up pack was installed".
The NBN is meant to be completed by 2020, and Infrastructure Australia has urged the network to be privatised in the medium term.
The full report can be viewed here.
In its most recent release, the TIO said there was a total 2,176 new NBN-related complaints between October and December, a 40.1 per cent lift on the same period in 2014, but a 3.8 per cent fall from the previous quarter.
The TIO noted that in the 3 months to December an extra 123,619 premises were connected to the NBN.
A spokesman for the NBN said the organisation "acknowledges we don't always get it right".
"We are however pleased with the reduction of 3.8 per cent from the previous quarter against a growth in connections to the NBN network of more than 20 per cent," he said.
"The number of complaints per 100 connections is going down if you consider the rapid rise in connections over the past year.
"At 31 December 2015, the NBN network footprint extended to over 1.6 million homes and businesses with 736,052 connected to the network. We’re now activating more than 13,000 new users every week."
On the broader sector, the Ombudsman said total telco complaints fell almost 10 percent in the last three months of the year compared to Q3, despite the downbeat picture on the NBN.
“I welcome the continuing drop in mobile and landline complaints, but internet service providers need to be on alert about internet fault complaints,” acting ombudsman Diane Carmody said.
“The majority of complaints about unusable NBN services happened during the first few weeks of consumers transferring their services from copper to the NBN and 90 percent were resolved after the TIO referred them back to the telco".
The NBN said: "Any disruption of service is regrettable, and we encourage all consumers to contact their retail service provider to ensure services are restored quickly.
"For customers migrating from existing networks to the NBN network, the Federal Government’s recent Migration Assurance Policy will help ensure a more seamless transition," the spokesman said.
"Battery backup is available in some cases, however, like any powered equipment, the NBN network should not be relied on in a power outage. Consumers are encouraged to discuss battery back-up or service continuity options with their retail service provider."
This story has been updated to include a response to the Ombudsman's report supplied by the NBN. An earlier reference to a PWC report about the value of the NBN has been removed due to the report's inaccuracy.