More Australians hitting the South Island's ski slopes has visitor numbers up 40 per cent on all previous records, NZSki says.

The company, which operates the Mt Hutt, Coronet Peak and Remarkables ski fields, says the boom is due to big investments in infrastructure along with the introduction of cheap airfares.

"Last year we were in a technical recession and our board still invested in excess of $30 million, and that's what we're all enjoying right now," NZSki chief executive James Coddington told NZPA.

The cash paid for snow-making systems and a new base building at Coronet Peak, without which they wouldn't be coping with the rush, Mr Coddington said.

"We had all of that in the last year, so obviously (people) went back and told their friends."

He said the increase was entirely down to Australia where an advertising campaign had been running, with local visitor numbers holding steady with last season.

The introduction of a new trans-Tasman airline, plus increased capacity on existing carriers, had made New Zealand more accessible, Mr Coddington said.

"Now we've got Jetstar offering very affordable fares, prior to the season they were offering $29 fares and I believe they're now $89.

"Before, if you were lucky you might get down to $400 one way.

"It's also easier. If you're in Queensland or New South Wales, you can jump on a plane, you can be there in three hours and be on the slopes the same day."

"In Australia it's between a six and eight hour drive for them (to most fields)."

Mr Coddington said ticket prices which translated to about A$63 ($79) versus A$102 in Australia brought the cost down further - meaning tourists had more cash to spread around.

Barry Ellis, who manages a company operating three Queenstown bars, said it had been one of the best winters in 20 years.

"We're as busy as everybody else is. It's as good a ski season and commercial winter season as we've had," he told the Southland Times.

Browns Ski Shop owner Kris Vermeir agreed.

"It's too early to count our chickens because we still need a good September, but so far it's breaking all records."