That figure is set to nearly triple in the next 20 years, with the airport's master plan, due to be released in March, forecasting 8.9 million passengers will fly out of Canberra in 2040.

Singapore Airlines and Qatar Airways collectively connect Canberra to more than 180 international airports, with plans in the works to introduce direct flights to New Zealand and China in the next five years.

Further north, Sydney saw about 44.4 million passengers through its airport in 2018-19, up from 44.03 million the year before. In the next 20 years, Sydney passenger numbers are forecast to grow. The airport forecasts it will host 65.6 million per year by then.

International passengers will be the main driver for Sydney's growth with roughly even numbers departing overseas as catching domestic flight by 2039.

While Canberra Airport operators intend to extend its international offering, an ongoing push will continue to target regional passengers in its bid for the domestic market.

Craig Jacques lives in Orange, which is 268 kilometres from the Sydney Airport and 264 kilometres from the Canberra Airport. While his international travel often requires a Sydney departure, when flying domestically he chooses the ACT.

"It's an easier drive to Canberra," Mr Jacques said.

"The roads have gotten better through Boorowa, it's about the same time, there's no tolls and parking is heaps cheaper and easier."

The miners who regularly fly in and out of Mr Jacques home town do so through the city's small regional airport, with the 50 minute trip to Sydney typically costing between $450-$500 return.

Mr Jacques said the expense was more of a deterrent than the 3.5 hour drive to Sydney or Canberra. He said if the ACT was better connected internationally his family would road trip south for their regular flights to Canada, rather than over the Blue Mountains.

"It's a lot less busy and it's definitely a lot easier. I'd definitely look at [international flights] if more options were available," he said.

According to transport department figures, the number of passengers and aircraft at Canberra Airport has grown by 4.4 per cent over the past three years. Sydney has seen a 2.6 per cent growth.

Canberra Airport's attractiveness to travellers outside the ACT has not been accidental, with operators marketing its convenience to travel agents, local government and media outlets in Goulburn, Snowy Mountains, South Coast, Southern Highlands and Wagga Wagga for the past four years.

Canberra Airport head of aviation Michael Thomson said since Singapore Airlines started flights from Canberra in 2016, attracting travellers from surrounding regions had been a key priority.

"People are time-poor, and it's an easy drive to Canberra from all of the towns in our region," Mr Thomson said.

He pointed to parking, lack of queues, efficient passenger handling and an improved retail and food experience "with more opening in the coming months" as part of what made the airport attractive.

"The next five years for us is about driving aviation growth through more international carriers and more domestic routes, particularly through low-cost carriers."

Of the Australian residents who flew into Sydney from overseas in the year ending November 2019, 84 per cent lived in NSW. For residents flying into Canberra Airport during the same period 83 per cent lived in the ACT and 16 per cent were from NSW.

Canberra Airport-commissioned research found 60 per cent of people within one hour of the capital would prefer to fly out of Canberra.