The association said in a post on its website that it filed the application for a vote among the company's more than 1,200 pilots on Monday.
If the application is approved, the industrial relations board is expected to oversee a secret ballot vote of all eligible WestJet pilots to determine support for creating a legally recognized union.
The association said in its post that one of the requirements for making the application for a certification vote is a demonstration of more than 40 per cent support for the WPPA in membership card count.
The WPPA says it exceeds that threshold.
Also on HuffPost: