Air routes into and around WA are booming while the rest of the nation's passenger traffic has fallen in the past year, figures show.
Department of Infrastructure and Transport statistics show that while overall Australian domestic passenger traffic rose just 0.4 per cent last financial year to 54.98 million, activity at Perth Airport jumped 11.5 per cent.
The major factors influencing the boom and bust in air travel were the resources industry in WA and the grounding of Tiger Airways in July last year.
The biggest gains in WA were the Newman to Perth route, which was up 36.5 per cent, Perth to Port Hedland, up 29.9 per cent, and Brisbane to Perth, up 15.5 per cent.
In the past seven years, Perth Airport recorded an average annual growth rate of 9.3 per cent, putting a big strain on infrastructure.
Starting in January, more than $750 million will be spent on new terminals and expanding facilities to handle demand.
In 2015, the first stage in a $1 billion airport freeway upgrade will be finished to help solve traffic bottlenecks.
For the year ended June 30 this year, Melbourne to Sydney remains Australia's busiest route with 7.73 million passengers, a 2.3 per cent fall compared with the previous year.
It was followed by Brisbane to Sydney with 4.35 million passengers, down 2.2 per cent, and Brisbane to Melbourne with 3.15 million passengers, up 1.3 per cent.
Sydney remains Australia's busiest domestic airport with 24.2 million passenger movements, followed by Melbourne (21.42 million), Brisbane (16.44 million) and Perth (8.5 million).
However, the Perth figure does not include the estimated one million mainly fly-in, fly-out passenger movements through the terminals of Skippers Aviation, Network Aviation and Cobham.
International passengers through Perth Airport rose 6.5 per cent to 3,492,160.