Stena Line is offering over a million free child places for ferry travel to Ireland from Britain any time this year.
Free places are available on any standard single or return booking made before March 28th for people travelling by car and staying for longer than five nights.
There are no restrictions on time, day or month of travel and families can travel on any Stena Line vessel.
Stena head of marketing in the UK Ms Julia Fothergill said: "With short-haul destinations such a popular choice this year, we thought the time was right to add another reason for choosing Stena Line and Ireland".
The offer - on crossings from Holyhead to Dun Laoghaire and from Fishguard to Rosslare - includes cars and people carriers, carrying up to eight passengers.