The accident happened Saturday about 2,400 metres (7,800 feet) up in the Lungau district, soon after 1:45 pm local time, Red Cross spokesman Anton Schilcher told the APA agency.
The snow buried eight of the group up to 4.5 metres deep, local emergency response official Christoph Wiedl told local media.
Two of the victims were already dead when their bodies were recovered, while the third died after being airlifted to hospital in Klagenfurt.
The two injured skiers were taken to hospital in the town of Tamsweg.
The skiers caught in the avalanche were from a group from the regions of Salzburg and Upper Austria.
In recent years, an average of around 20 people a year have been killed annually by avalanches in Austria.
The last two seasons were less deadly as the coronavirus pandemic reduced the number of skiers overall.
Avalanches killed four people in western Austria’s Tyrol region last February.