Delta Air Lines completed the integration of the Northwest Airlines reservations system.

Described by Delta as "one of the final merger milestones" following its acquisition of Northwest in 2008, the switch involved officially retiring the Northwest flight codes and consumer booking Web site, and moving all Northwest passenger records into its system. "Customers who booked Northwest for travel are now booked on identical Delta flights," according to a Delta statement. "Delta has increased customer service agent staffing in airports and reservation call centers this week to ensure a smooth experience for customers."