A total of 451 people are being made redundant: 264 in Krakow, 120 in the UK, 60 in Majorca and 7 in Switzerland.
Smith & Williamson LLP and CMB Partners UK said that there were exhaustive attempts by the directors to rescue the group.
Finbarr O’Connell of Smith & Williamson said: “The group experienced significant market headwinds in the run up to the EU referendum as holidaymakers delayed decisions. This was compounded by the Leave vote itself and the subsequent fall in value of the pound.
“Regrettably, in these extraordinary conditions, the directors had no option but to place Lowcosttravelgroup Limited into administration.