Representatives from 17 of the airline’s bases around Europe wrote to their employer to make it clear they were not tempted by the offer, instead demanding better contracts and working conditions, the BBC reports.
Pilots were offered £12,000 or €12,000, while first officers were offered half as much to take on extra shifts.
Ryanair admitted on Monday that the company had "messed up" in creating a situation that led to 400,000 customers having their flights cancelled at short notice.
The pilots’ letter reads: "The pilot market is changing, and Ryanair will need to change the ways which the pilots and management work together to ensure a stable and common future for everyone."
It added that improved contracts would help to slow down the large number of Ryanair pilots choosing to leave for "greener pastures".
Some pilots have claimed that Ryanair has a pilot shortage, with many choosing to leave for rival airlines – though speaking on Monday, chief executive Michael O'Leary insisted this was not the case.