The airline flew home hundreds of passengers from Cancun, Mexico and St. Martin on Sunday night.
But those passengers weren't able to pick up their bags and some waited hours to do so.
Karen Porpealia and her young family spent the night in Terminal 1 and missed their connecting flight home to Sudbury, Ont., as they waited for their luggage.
"I have a baby here who's down to two diapers and a daughter in socks and a husbands in shorts and our coats are checked somewhere in with our luggage [along] with our car keys," Porpealia told CBC News.
The airline told CBC News that the cold weather was to blame.
"Due to the extreme cold, Pearson Airport experienced service delays and interruptions which impacted aircraft servicing and baggage handling," said Janine Chapman, the vice-president of marketing for Sunwing Travel Group. "The impact of this issue was certainly not isolated to Sunwing Airlines, however we can confirm that customers returning on our Cancun and St Martin flights last night were affected."
Chapman said that bags had been returned to 80 per cent of the luggage had been returned to customers.
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