Holidaymakers, including Anne Rymer from Wakefield, said they were handed leaflets when they arrived at the airport on Monday morning, while others found out as they were queuing to check in.
Ms Rymer, 71, praised airport staff for the support she and others received on arriving for her flight.
She said: “I got here at 5.45am and was given a leaflet.
“The rep from the Civil Aviation Authority, Mark Johnson, was here straight away and he was brilliant and really helpful.
“I had booked to go to Menorca with Saga and have been told they should be able to get another flight later today.
“Some other people have been a lot worse off.”
Denise Parry, 51, from Salford, said she had been forced to cancel her holiday to Turkey after she tried to book on to another flight but was then told it was full.
She said: “We got to the airport at 3am and it was at 4am while we were in the queue that we found out.”
Ms Parry and her partner initially booked alternative flights to Dalaman with Thomson later on Monday but she was later told no more places were available on the plane.
She said: “It is so annoying, we have had the holiday booked for 12 months.
“We’re going home now.”
Tim Gausden, from New Moston in Manchester, said he was in the taxi on his way to catch a flight to Malaga in Spain when he heard the news on the radio.
He said: “We were halfway down the motorway when we heard the news.
“When we got here staff were handing out leaflets. They were Monarch staff and they just looked fed up, but they were doing their best.”
He said tour operator CITO, with whom he booked the holiday, had arranged alternative flights for Monday evening.
Roger Smith, 69, travelled from Shrewsbury on Monday morning to catch the same flight as Mr Gausden.
He said: “We got here about 4.30am and the guy who marshalling at the drop-off just said ‘If you’re travelling with Monarch, forget it’.
“Luckily our agent has sorted out alternative flights for 8pm.”