E ffective as of January 1, 2015, you can enjoy the benefits of a reciprocal partnership between WestJet and Delta Air Lines where you can earn or redeem your choice of either SkyMiles or WestJet Dollars regardless of whether the operator of the flight is Delta Air Lines or WestJet.
Unfortunately, earning elite level status is not part of this reciprocal partnership, as flights operated by WestJet will be ineligible for earning both Medallion Qualification Miles and Medallion Qualification Dollars towards elite level status in the SkyMiles frequent flier loyalty program; and flights operated by Delta Air Lines are not eEligible towards annual qualifying flight spend on WestJet.
Here are the charts from both WestJet and Delta Air Lines:
This reciprocal partnership — despite its shortcomings — will give members of the frequent flier loyalty programs of WestJet and Delta Air Lines more flight and destination options within the United States and Canada.