Aer Lingus staff are to receive 10% of revenue collected from new charges for bags checked in at airports.
The deal, which will boost salaries for check-in staff, was agreed at the Labour Relations Commission last night.
Aer Lingus declined to say how much the new commission system would cost.
From Wednesday 17 January, Aer Lingus passengers who check their bags in at the airport must pay €8 per item of checked luggage.
Under this new deal, the check-in operator will receive commission worth 10% of the revenue collected, i.e. 80c for each bag handled.
However, they will not receive commission on lower baggage charges paid by passengers checking in on the Internet.
For the first year of the new scheme, each check-in worker is guaranteed a payment of at least €1,000.
SIPTU is recommending that its members should accept the deal in a ballot which will be completed by Wednesday.
Check-in staff already receive a 10% commission on all excess baggage charges which they collect.
A spokesperson for Aer Lingus described last night's deal as a continuation of its current policy of paying staff commission for collecting check-in and excess baggage charges.
However, the spokesperson would not reveal how much the commission system is set to cost the airline - at a time when it has repeatedly said it is focussing on cutting costs.
A spokesperson for Ryanair said that they do not operate a commission system at their check in operation.
However, staff receive bonuses based on reaching performance targets.
