A flight that costs around €400 now could drop to as little as €50 in January.
Air & Travel Magazine Editor Eoghan Corry has been taking listeners' questions on festive travel.
Dublin Airport has said around 1.5 million passengers are set to travel through the two terminals over the festive period.
The peak Christmas travel period between Monday, December 18th and Friday, January 6th will see more than 75,000 passengers pass through the airport every day.
Irish airports will close to passenger traffic on December 25th, while Shannon Airport will remain open for emergencies.
Eoghan told Lunchtime Live people should travel before or after Christmas Day.
"The run in to Christmas is the cheapest time of the year to travel," he said.
"It's the cheapest time for flights, it's the cheapest time for hotels.
"Whether you're going to the sun - really the sun option at this time of the year is the Canaries - or the ski resorts, and we've got some of the best pre-Christmas snow we've had in years.
"All of that is cheap because everyone is concentrating on Christmas.
"Then it gets really expensive at Christmas and then it sort of reasonably plateaus again in January.
"If you look through the prices of the year, the first two weeks of December are always the cheapest."
'Demand outstrips supply'
Eoghan said one example would be a flight to the Canary Islands.
"You will be paying €400 one-way for a flight before Christmas that, if you were to wait till after New Year's Day, the same flight would cost you €50," he said.
"It really pushes prices through this awful peak at Christmas, and there's no escaping it.
"Basically demand outstrips supply, and supply is reduced for winter.
"From the end of October to the end of March, the number of flights comes down by about one-third.
"It doesn't make sense for an airline to put all the aircraft back in the sky for two weeks at Christmas.
"They would love to do it because they could make money off it, but it just doesn't add up".
Eoghan said taking a flight through the New Years Eve countdown is another way to save money.
"Everybody flying through the night, the prices drop".
Eoghan said he would always recommend booking with airlines directly, rather than an intermediary such as Skyscanner, but these can be used for price research.
