“Lauda deeply regrets the loss of more than 300 jobs for its A320-team and the closing of Lauda's A320 base in Vienna on Friday May 29,” the carrier said.
Ryanair had earlier threatened to close the base if it could not get agreement on salary cuts for Laudamotion employees in Vienna.
The airline has three other smaller bases — two in Germany, in Dusseldorf and Stuttgart, and one in Palma de Mallorca in Spain.
Vida, a trade union representing workers in the transport and service industries in Austria, refused to agree to a contract that stipulated reduced wages for Laudamotion employees.
It said the proposed entrance salary for board personnel was below the country's guaranteed minimum income.
Ryanair said Monday that annual profit sank as the coronavirus halted travel and the Irish no-frills airline bet on jet fuel prices being much higher ahead of an oil-price crash.
Laudamotion was founded by late Formula One legend Niki Lauda, and Ryanair bought it in 2018. Lauda died a year ago at age 70.