Before 2004, the NASCAR Cup Series champion was determined by accumulated points across the full season, a system that occasionally produced a mathematical champion well before the final race. NASCAR and sponsor Nextel announced the new playoff format on January 21, 2004, citing the goal of sustaining fan interest and television ratings through the autumn, a period that coincides with the start of the NFL and college football seasons and the MLB postseason.
The system is informally known as the "Matt Kenseth Rule," a reference to Kenseth's 2003 championship, which he secured with just one race win but 25 top-ten finishes. Ryan Newman won eight races that same year but finished sixth. While NASCAR has stated the 2003 outcome was not the sole driver for the change, the coincidence of Kenseth's title and the playoff's introduction in 2004 made the association commonplace in media coverage.
Inspiration for the format is partly traced to the United Speed Alliance Racing's USAR Hooters Pro Cup Series, which introduced a five-race playoff in 2001 — a system NASCAR studied before devising its own version.
After 26 regular-season races, the top 10 drivers (plus any others within 400 points of the leader) entered the Chase. Points were reset, with the leader starting at 5,050 and each subsequent driver receiving five fewer points.
The Chase field expanded to 12 drivers, with each driver's points reset to 5,000 plus a ten-point bonus per regular-season win. The 400-point provision for additional qualifiers was dropped. NASCAR chairman Brian France cited a desire to place greater emphasis on winning races.
The top 10 drivers automatically advanced to the Chase, joined by two wild-card qualifiers — the two drivers ranked 11th through 20th in points with the most wins. Points reset to a base of 2,000. In 2013, a match-fixing controversy at Richmond International Raceway, involving Michael Waltrip Racing's deliberate spin and manipulation of the finish, resulted in NASCAR expanding the field to 13 drivers for that season only. Gordon was added after NASCAR determined he had been placed at an unfair disadvantage by collusion between MWR and Penske Racing.
A substantially revised format introduced elimination rounds, expanding the Chase field to 16 drivers. Three cutoff races reduced the field in stages: from 16 to 12 after the Challenger Round, from 12 to 8 after the Contender Round, and from 8 to 4 after the Eliminator Round. The four remaining drivers had their points equalized at 5,000 heading into the finale at Homestead-Miami Speedway, where the best finisher among the four was crowned champion. Any Chase driver who won a race during a playoff round automatically advanced to the next round regardless of points standing.
Renamed the NASCAR Playoffs, the format retained the 16-driver field and elimination structure. A revised stage-based points system was introduced, splitting races into three stages and awarding bonus points for stage wins during the regular season. A separate "playoff points" currency was introduced to determine seeding and carry bonuses into the postseason. The regular season champion received additional playoff points. A regular season championship was also formally recognized for the first time.
Lower series (Xfinity, Truck) adopted their own playoff formats from 2016, using smaller fields and fewer rounds.
Following significant criticism — particularly after the 2025 season finale at Phoenix, where multiple title contenders expressed frustration with the one-race-decides-all format — NASCAR revamped the system and reverted to calling it The Chase. The 2026 format retains 16 qualifiers but removes the bracket-style eliminations, win-and-you're-in qualification, and playoff points. Points are reset to a minimum of 2,000, with the regular season champion receiving an additional 100 points and positions 2–15 receiving graduated bonuses. Homestead-Miami returns as a season finale host under a new rotational system.
The format has attracted sustained criticism as an artificial "gimmick" that can produce a champion who did not dominate the full season. The 2020 season is frequently cited: Kevin Harvick won nine races with an average finish of 7.1 but was eliminated at Martinsville after contact from Matt Kenseth caused a tire failure on the final lap. Harvick stated the system was "skewed more towards entertainment" than rewarding season-long performance. Following the 2025 Phoenix race, in which Denny Hamlin dominated but lost the title on a late restart, criticism reached a peak that contributed directly to the 2026 format change.
Other criticisms include broadcast coverage disproportionately focused on playoff contenders even when they have crashed out, and the format's incentive for aggressive or manipulative behavior in must-win scenarios. The 2013 Richmond race and the 2024 Xfinity 500 are both cited as examples where the win-or-advance structure encouraged conduct detrimental to the sport.
Since 2004, ten different drivers have won the Cup Series title under the playoff format. Jimmie Johnson won seven championships under the system. Tony Stewart, Kyle Busch, Joey Logano, and Kyle Larson each won multiple titles in the playoff era.
The Xfinity Series (now O'Reilly Auto Parts Series) and Craftsman Truck Series received their own playoff formats starting in 2016, using 12 and 10 drivers respectively across nine and seven races. The Truck Series expanded its field from 8 to 10 drivers in 2020. Both series adopted the same Chase structure revamp in 2026 alongside the Cup Series.