AER Lingus still has the fifth-highest costs per employee among European airlines, despite pay cuts and freezes in the past four years.
A survey by international aviation group CAPA said the cost per employee at Aer Lingus was €74,818 on average, way above the average at Ryanair, where the average is €49,182.
The most expensive employees are at the troubled Scandinavian airline SAS, where the average is €104,342.
British Airways is at number nine, at €66,851. That is lower than Easyjet, where the average is €70,472.
The research is published as airline bosses, including Willie Walsh, the chief executive of IAG, which owns British Airways and Iberia, and Aer Lingus boss Christoph Mueller gather at a two-day international aviation think-in in Co Wicklow, organised by CAPA.
"How much it costs to keep an employee at work is not just a function of wages, but is also affected by the level of social charges, the seniority mix of employees and the level of pension contributions – all areas in which unionisation and history can play a major part," notes CAPA.
When he took over as chief executive of Aer Lingus in 2009, Mr Mueller embarked on a radical cost-reduction programme that has shaved more than €100m a year from the airline's cost base.
Labour costs as a percentage of revenue at Aer Lingus – at 19.2pc – are just over twice as much as they are at Ryanair, where the figure is 9.5pc. But despite its tight cost controls, Ryanair is ranked the third-lowest on the scale. The airline with the lowest labour costs as a percentage of revenue is Wizzair, at 6.5pc, with Spain's Vueling second-best at 8.6pc.
Vueling yesterday agreed to accept an offer from IAG to acquire the 54pc of the company that it doesn't already own.
Speaking at a tourism event in Abu Dhabi yesterday, Mr Walsh said he had no plans to merge Vueling with Iberia.
IAG is targeting 3,000 job cuts at loss-making Iberia and wants to slash salaries there in order to return the business to profitability.
IAG will use Vueling to increase its short-haul business and compete more efficiently with low-cost operators, including Ryanair, which is the biggest carrier in Spain.
Labour costs as a percentage of revenue at Iberia stand at 30pc, according to CAPA.
The amount of revenue generated for each employee on the books stands at €520,265 at Ryanair – the fifth-best in CAPA's survey. The best is Vueling, at €629,566. At Aer Lingus, the figure is €390,634.