A WestJet flight taxis for takeoff from Calgary, but it won't be taking contest winners on a tropical vacation. The airline says phone calls to people promising such a prize are a scam. ((Todd Korol/Reuters))

Tens of thousands of Canadians are getting phone calls saying their customer loyalty has earned them the prize of a free vacation, but the company most often named in the calls, WestJet, says it's all a scam.

The airline wants to ensure that none of its customers fall for it.

"It's called a pitch scam," WestJet spokesman Robert Palmer told CBC News. "Basically you're phoned by a telemarketer, someone posing as an employee of a company. WestJet is one of a half a dozen different companies variously being mentioned in this."

Consumers throughout the country are getting the calls. WestJet said numbers are being randomly dialed, resulting in calls to homes, businesses and cellphones.

"Basically the telemarketer takes you through a series of questions in order to gain your confidence. They ask you if you have a credit card, and of course the purpose of this is to get credit card information from you," Palmer said.

'We don't engage in telemarketing schemes.' —Robert Palmer, WestJet

Fraud prevention experts warn consumers never to give their credit card number to a stranger who calls. They also say consumers should never have to spend money, or give a credit card number in order to win a prize.

Palmer said WestJet has been hearing from its customers.

"They've contacted us to ask, 'Is this really you,' and of course it's not. We don't engage in telemarketing schemes. We don't share private information of our guests with third-party people for the purpose of telemarketing."

Anyone receiving a call is urged to contact the Canadian Anti-fraud Call Centre at 1-888-495-8501.