Australians are still suffering from budget airline Bonza's unreliability a year after its launch.

The carrier's overall arrival time improved in January with 78.4 per cent of planes arriving on schedule, in stark contrast to just 55 per cent in December, according to new data from the Bureau of Infrastructure and Transport Research Economics (BITRE).

But the same report found Bonza was the least reliable airline to get passengers on time to Melbourne, Gold Coast, Sunshine Coast and Mildura airports last month.

The BITRE report included on-time performance per airport — including cancellations, arrivals and departures — for domestic routes for which the passenger load averaged 8,000 per month over the previous six months, and where two or more airlines operated in competition.

CEO: 'We have learnt'

Bonza's December cancellation figure did not include the mass cancellation of all Darwin to Gold Coast flights due to a delay in the opening of Bonza's newer flight routes.

In the same month, the carrier had the highest rate of cancellations at 19.4 per cent, followed by Skytrans at 9 per cent and Virgin Australia at 7.7 per cent.

Bonza CEO Tim Jordan said the airline hoped to do even better.

"We have learnt and vastly improved from our December 2023 cancellations and OTP,  which mostly arose from the well-publicised delays in receiving regulatory approval related to aircraft operating out of our new Gold Coast base,” he said in a statement.

In the February domestic airline competition report, the ACCC said Bonza had improved regional connectivity but also noted its performance was "highly variable". 

"The airline demonstrated that it could effectively service its expanding network with its performance during the August–October period," the report stated.

"Cancellations spiked significantly between June and July 2023 and then again in December 2023."

Anxious to travel

It's not often 56-year-old Sue Heenan — manager at a busy club in Tumbling Waters, 60 kilometres south of Darwin — gets a chance to take a vacation.

Ms Heenan booked tickets immediately after the budget airline launched return flights between Darwin and the Gold Coast for less than $300 in November 2023, hoping she and her husband could visit their newly-born grand-niece on the east coast.

"Living in Darwin, flights are really expensive to go anywhere and we have very limited options," Ms Heenan said.

The loved-ones are still yet to meet, after Bonza scrapped all flights between Darwin and the Gold Coast until March 20, 2024, less than 24 hours before the husband and wife were set to fly.

It took two months before the couple were refunded $574 for their flights, which is more than one month late, according to Bonza's refund policy.

The married couple are still $1,300 out of pocket for babysitter, accommodation and car rental fees which were non-refundable.

Mass cancellations

More than 100 people have banded together on a social media forum called "BONZA SCUM OF THE AIR", sharing stories of monetary-losses and plans ruined due to Bonza disruptions.

Bundaberg resident Rodney Keenan created the social media group after he was left "financially burdened" by the airline, after a return flight to his hometown was cancelled.

As a result of the cancellation, Mr Keenan said he incurred costs for accommodation, two fares with Virgin and a one-way car hire totalling more than $2,000.

"It took me two months and a credit card dispute to finally secure a refund, after sending six ignored emails to Bonza and spending endless hours waiting for a response via their chat app," he said.

In a statement, Bonza chief executive Tim Jordan said the December delays were "well publicised".

"We have learnt and vastly improved from our December 2023 cancellations and [on-time performance]," Mr Jordan said.

Owner's legal battle

Bonza offered the ABC several different reasons for the airline's unreliability over the past six months, including bird strikes and compliance issues.

The legal battle its owner, 777 Partners, was fighting overseas was not one of them.

In March 2023, three lessors took legal action and repossessed four planes leased to 777 Partners for use by Flair Airlines, due to $US2.2 million in outstanding rent and interest.

777 Partners consequently gave Flair multiple planes, which were originally meant to be leased to Bonza.

Two of Bonzas six aircraft are still wet leased to Flair Airlines.

Bonza declined to comment about whether the legal proceedings affected its service in Australia.

A 777 Partners spokesperson said the ongoing legal proceedings did not affect Bonza.