The 2004 NASCAR Nextel Cup Series was the 56th season of professional stock car racing in the United States and the 33rd modern-era Cup series season. The season began on Saturday, February 7, and ended on Sunday, November 21. Kurt Busch, who drove a Ford for Roush Racing, was the Nextel Cup champion. It would be the last time until 2012 that the championship would be won by someone other than Tony Stewart or Jimmie Johnson.

This was the first season that NASCAR utilized the Chase for the Nextel Cup format that began with the Sylvania 300 on Sunday, September 19. Under the format rules, the top 10 drivers (and any additional drivers within 400 points of the leader) by the end of the 26th race would be eligible to compete in a final 10-race playoff to determine the NASCAR Nextel Cup champion. Following the 26th race, the eligible drivers would have their points reset to bring the drivers closer together in the standings, with only five points separating each driver. The season would then continue as normal, with the driver with the most points at the end of the season becoming the champion.

The NASCAR Manufacturers' Championship was won by Chevrolet when they captured 26 wins and 266 points. Ford finished in second place with 10 wins, and 224 points, while Dodge followed in third with 4 wins and 194 points.^[1]

This was the first year for the new series sponsorship. Mobile phone provider Nextel assumed sponsorship of the NASCAR championship series from cigarette brand Winston. Winston was the title sponsor of the Cup Series for 33 seasons, from 1971 to 2003. Nextel would become only the second title sponsor in Cup Series history. This was also the first year for Sunoco as it replaced Unocal 76 Brand as the official fuel of NASCAR. Sunoco would become only the second gas company to be NASCAR's official fuel since Unocal had been the official fuel since the sport's inception in 1948.

The season was also marked by tragedy. On October 24, a charter airplane owned by Hendrick Motorsports crashed at Bull Mountain in the Blue Ridge Mountains of Virginia, near Martinsville Speedway. Ten people aboard the plane died, including four relatives of team owner Rick Hendrick, as well as Randy Dorton, Hendrick's chief engine builder. Jimmie Johnson, a Hendrick driver, had won the race, but the post-race victory ceremony was canceled as words spread of the incident.

2004 was the first season without Jerry Nadeau since 1996, Brett Bodine since 1985, and Pontiac (though a few Pontiacs without factory support ran several early-season races).

It was the last season until 2021 without Clint Bowyer and Reed Sorenson and the same time before Denny Hamlin joins NASCAR as a driver (he ran the last 7 races in 2005 before joining full-time in 2006).

Teams and drivers

Full-time schedule