Beginning Monday, December 8, 2025, New York City’s F and M subway lines will undergo a major weekday shake‑up between Queens and Manhattan. On weekdays from about 6:00 a.m. to 9:30 p.m., the Metropolitan Transportation Authority will permanently swap the routes the F and M take between the Queens Boulevard line and Midtown tunnels, changing which trains stop at eight key stations and affecting an estimated 1.2 million daily riders. MTA+2MTA+2 The change, dubbed the “F/M swap,” is designed to untangle a notorious track merge near Queens Plaza that has been responsible for a significant share of rush‑hour delays on the E, F, M and R lines. Officials say that by simplifying how lines share tracks, riders should see fewer bottlenecks, more consistent running times and less crowding—though many commuters are bracing for confusion and potential longer trips, especially at Roosevelt Island and along the 63rd Street corridor. New York Post+3NY1+3NBC New York+3