Delta Air Lines has officially completed its acquisition of a 12.7% stake in Canadian carrier WestJet. The transaction was part of a broader deal where Onex Partners sold a combined 25% interest in WestJet to Delta, Air France-KLM, and Korean Air. The deal, which was first announced on May 9, 2025, closed on October 22-23, 2025. This strategic investment solidifies the partnership between the airlines and is aimed at improving global connectivity for travelers, particularly within the SkyTeam Alliance. While Onex Group will retain a 75% controlling stake in WestJet, the move signals ongoing consolidation and alliance-building within the airline industry. Market reaction to the finalization of the deal has been described as uncertain to mildly positive.