Prior to Tuesday's announcement, the airline said it had 14,000 employees.
WestJet has cut its workforce in half as 6,900 people received notices today confirming early retirement, early outs, and both voluntary and involuntary leaves.
"This is devastating news for all WestJetters".
According to the brief, the airline issued a communication across the company requesting that employees volunteer to "support the survival of the airline" by opting for one of several options, including an unpaid leave of absence, early retirement, voluntary resignation (early out), reduced working times, or reductions in pay.
"The fact that we avoided a potentially worse outcome is testament to the spirit and selfless attitude demonstrated by our people, who have enabled WestJet to continue operating with a collective remaining workforce of 7,100", Sims said in a blog post on Tuesday.
Air Canada announced last week to lay off more than 5,100 flight attendants, as the country's largest airline cut routes and parked planes after many countries in the world had closed their airports to contain the COVID-19 spread.
WestJet announced that 6,900 of its staff would be leaving the organization - with 90% doing so voluntarily - in response to the decrease in business and cost-cutting measures brought by the COVID-19 pandemic. This was on top of measures to suspend commercial operations of worldwide and trans-border flights.
The executive team of the Calgary-based airline has taken a 50 percent pay cut, while the vice-presidents and directors have had their pay cut by 25 percent.
"We could not have achieved what was required without the support and collaboration of our union leadership and the leaders of our employee associations", said Sims.
Earlier this week Transat AT announced it was laying off 3,600 employees.
Around 7,100 workers remain on the job.