The $51 billion National Broadband Network will be completed on time and on budget by June this year, the infrastructure project's chief executive Stephen Rue has confirmed, as the company's half-year loss soared past $2 billion.

Key points: In the six months to December 31, NBN Co reported total revenue of $1.8 billion

In the six months to December 31, NBN Co reported total revenue of $1.8 billion But the company posted a $2.14 billion loss due to increasing subscriber costs

But the company posted a $2.14 billion loss due to increasing subscriber costs An additional 907,000 residential and business premises were activated in the six months, lifting total activations to 6.4 million

The next few months are critical for the NBN Company in the face of persistent consumer complaints.

But with the project now 90 per cent complete, Mr Rue stuck to his pledge, made in August last year, that the June 2020 deadline would be met.

In the six months to December 31, NBN Co reported total revenue of $1.8 billion, up 39 per cent on the same period last year, and earnings before tax of $775 million.

An additional 907,000 residential and business premises were activated in the six months, lifting total activations to 6.4 million.

Average revenue per user (ARPU) rose to $45 from $43 per month.

However, the project recorded a net loss after tax of $2.8 billion, adding to consecutive multi-billion dollar losses in recent years.

The company posted an earnings before interest and tax (EBIT) loss of $2.14 billion for the half year due to increasing subscriber costs.

Subscriber costs for the half year were $1.43 billion, up from $690 million in the previous period.

According to the results released this morning, the loss is in line with expectations given the current stage of the business and "significant upfront investment".

NBN Co chief executive Stephen Rue described the results as "outstanding" and said the project was "well positioned" to be completed by June 2020.

"The progress of the rollout during the half was particularly pleasing, given we are now at the most challenging stage of the build which takes in more complex sites," Mr Rue said.

"We expect the urban rollout activity to further accelerate in the second half.

"We are very pleased to say that the NBN is now available in most areas of Australia, and customers continue to sign up to NBN services at a rapid rate."

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 9 minutes 52 seconds 9 m Can the NBN handle our ever-increasing digital appetite?

No need for taxpayer top-up of NBN budget: Rue

The peak NBN budget was increased to $51 billion in 2018 after higher costs and deferred revenue from delays in sites being completed.

The original $29 billion budget was topped up in 2017 by a special $19.5 billion loan from the Federal Government, which Finance Minister Mathias Cormann said was negotiated on commercial terms.

However, Mr Rue said he would not be seeking additional taxpayer funds to top up the NBN budget.

Communications Minister Paul Fletcher said the NBN project remained on track and was meeting its key financial and operational targets.

"NBN has laid out a clear plan to complete the rollout, and to do that within the available funding and financing, and today's results show that it is on track in accordance with its plan," Mr Fletcher told The World Today.

He said NBN Co was working to deal with the customer complaints which have beset the project.

"The company tracks customer service and customer experience and the statistics are going in the right direction," Mr Fletcher said.

"Of course, any time somebody has a bad experience, I'm concerned and the company is concerned. We want everybody to have the best possible experience."

Mr Fletcher, the member for Bradfield on Sydney's north shore, said he was connected to the NBN and was a satisfied user, despite complaints about quality and speed.

"I have the NBN at home and I am happy with it, yes, I am."

The NBN was initiated by the Rudd Labor government with an original blueprint to roll out a "fibre to the premises" service to about 98 per cent of premises by June 2021.

The Abbott government and then-communications minister Malcolm Turnbull changed the original strategy to include a mix of technologies including fibre, satellite and copper wire.