Australia's besieged NBN Co has moved its focus from the residential rollout to businesses, after complaints unreliable internet was having "a catastrophic effect" at some organisations.

Key points: NBN complaints increased by almost 160 per cent last financial year

NBN complaints increased by almost 160 per cent last financial year Some businesses have reported slower internet speeds since being connected

Some businesses have reported slower internet speeds since being connected NBN Co has announced several business-specific measures

Peak business and consumer groups have welcomed NBN Co's announcement it would establish a new team to work with the private sector and internet service providers (ISP) to better understand the needs of Australian businesses.

Teresa Corbin, the chief executive officer of the Australian Communications Consumer Action Network (ACCAN), said complaints about the National Broadband Network had increased by about 160 per cent in the past financial year.

"Business depends on their internet connection. Critically we find that when businesses lose their internet connection it can have a catastrophic effect," she said.

"If a complaint is not resolved and if a business is disconnected from the internet even for a few hours it means they cannot process payments both online and EFTPOS payments.

"This affects their bottom line and their ability to deliver services to their customers."

According to the Telecommunications Industry Ombudsman, there have been 27,195 complaints in the last financial year about the services delivered over the NBN.

Among the changes being announced by NBN Co are an improved connection process, with complex orders to be prioritised and case managed by NBN Co and ISPs.

More regional products, industry engagement and an education campaign focused on key business tools like EFTPOS and ATMs are also planned.

"We are committed to working with the industry to improve facilities for business," NBN Co spokesman Dan Chamberlain said.

"For the early years of the rollout we have really been focused on getting the consumer and residential side of the rollout right.

"What we are doing right now is setting up a new team dedicated to working with Australian businesses and service providers to understand the needs of Australian businesses."

Complaints about the NBN increased by about 160 per cent last financial year. ( Supplied: NBN Co )

'They find it slower than what they had previously'

Peter Strong, chief executive officer of the Council of Small Business Australia, said the council had been working with NBN Co to make it better.

"At the moment some of our members are being told to log on to the NBN and they find it slower than what they had previously had," he said.

"That is because the retail providers have not given them the correct information so they can make an informed decision.

"It is about being given the correct information so that business can be confident about their connection and make their plans.

"So we are going to fix that and we are working with NBN Co to monitor results and do that."

Ms Corbin has called for NBN Co to deliver service guarantees.

"There is no question the switchover has had an effect on productivity in Australia," she said.