NASCAR introduced the Strictly Stock division in 1949 following its earlier sanctions of Modified and Roadster racing. Eight races were held that inaugural year across seven dirt ovals and the Daytona Beach beach-street course. The first race took place at Charlotte Speedway on June 19, 1949; Jim Roper was declared the winner after the original finisher Glenn Dunaway was disqualified for having altered the rear springs on his car. Red Byron became the first series champion. The division was renamed Grand National for the 1950 season to project a more professional image, a name it retained until 1971. Martinsville Speedway is the only venue from the 1949 schedule that remains on the current calendar.
In the early Grand National years the schedule was extensive and loosely structured, sometimes exceeding sixty events in a year with races occasionally held the same day in different states. The vast majority of early races ran on dirt-surfaced short ovals. Darlington Raceway, opened in 1950, was the first fully paved track over one mile in length. Daytona International Speedway opened in 1959, yet even then the schedule still contained more dirt events than paved ones. The last Grand National race on a dirt track before a 2021 revival was held on September 30, 1970, at the State Fairgrounds Speedway in Raleigh, North Carolina.
In 1971, R. J. Reynolds Tobacco Company began sponsoring the series under its Winston brand, a development tied directly to the Public Health Cigarette Smoking Act of 1971 banning television advertising of cigarettes. Tobacco companies redirected advertising budgets toward sports sponsorships. The series was initially called the Winston Cup Grand National Series before "Grand National" was dropped in 1986.
Reynolds' involvement reshaped competition. Bill France Sr. handed control of NASCAR to his son Bill France Jr., the schedule was cut from 48 to 31 races per year, dirt-track events and short-oval races under 250 miles were removed, and a minimum prize purse per race was set at $30,000. In August 1974, France Jr. commissioned a revised points system awarding equal weight to all races regardless of length or prize money, ensuring top drivers had to compete at every event to challenge for the title. This system ran unchanged until 2004. The 1972 season is considered the start of NASCAR's "modern era."
The 1979 Daytona 500 was the first stock car race nationally televised live from flag to flag in the United States. Leaders Cale Yarborough and Donnie Allison collided while fighting for the lead on the final lap, allowing Richard Petty through for the victory. The subsequent on-track fistfight between Yarborough, Allison, and Bobby Allison on live national television, coinciding with a major eastern seaboard snowstorm that kept millions indoors, dramatically expanded the sport's audience. Since 1982 the Daytona 500 has been the first non-exhibition race of each season.
In 1985 Winston introduced the Winston Million bonus, offering one million dollars to any driver winning three of the four most prestigious races in a season. Only two drivers ever claimed it: Bill Elliott in 1985 and Jeff Gordon in 1997. In 1994 NASCAR held its inaugural Brickyard 400 at Indianapolis Motor Speedway. By 1999, NASCAR had signed an eight-year broadcast agreement with Fox, Turner Broadcasting, and NBC valued at $2.4 billion. The 1990s saw a major boom in the series' national popularity, though television ratings began flattening after 2000.
R. J. Reynolds terminated its sponsorship at the conclusion of the 2003 season. NASCAR signed with telecommunications company Nextel to take over for 2004, making the series the Nextel Cup. The 2006 Sprint-Nextel merger brought another rename to the Sprint Cup from 2008. The Sprint Cup trophy was designed by Tiffany and Co. in silver with a pair of checkered flags. Monster Energy sponsored the series for 2017–2019; the Monster Energy NASCAR Cup Series trophy stood three feet tall, weighed 68 pounds, was machined from aluminum over more than 300 hours of craftsmanship, and bore the outlines of all 23 Cup Series tracks on its exterior. NASCAR declined to extend the Monster deal beyond 2019.
The 2004 season also introduced the Chase for the Championship playoff format, seeding the top ten points earners from the regular season into a final ten-race shootout. The Chase expanded to 12 drivers in 2007 and was redesigned in 2014 into a four-round elimination bracket: a Round of 16, Round of 12, Round of 8, and a Championship 4, in which the highest-finishing of the four remaining contenders at the season finale wins the title. Stage racing was introduced in 2017, breaking each race into three scored segments with bonus championship points for stage winners.
From 2020 the series moved to a Premier Partner sponsorship model and adopted the current name. Premier Partners include Busch Beer, Coca-Cola, Xfinity, and Freeway Insurance. The championship trophy was renamed the Bill France Cup while retaining the design from the Monster Energy era.
In 2022 NASCAR introduced the Next Gen car — the seventh generation of Cup hardware — featuring fully independent front and rear suspension with double wishbones, centre-lock wheels, and a rear diffuser. A heavily modified Next Gen Camaro entered by Hendrick Motorsports competed at the 2023 24 Hours of Le Mans, finishing 39th of 62 starters.
The Drivers' Championship has been contested since 1949; 32 different drivers have won it. The record of seven titles is shared by Richard Petty, Dale Earnhardt, and Jimmie Johnson. Johnson additionally holds the record for most consecutive championships, having won five in a row from 2006 to 2010. All champions to date have been from the United States.
An Owners' Championship operates in parallel with the Drivers' title, awarding points to individual car entries. A Manufacturers' Championship is also contested: Chevrolet leads all manufacturers with 851 race wins and 42 manufacturers' championships, Ford ranks second with 728 wins and 17 titles, Toyota third with 180 wins and three titles, Dodge third with 217 wins and two titles.
Cup Series cars follow a front-engine, rear-wheel-drive layout with a roll-cage spaceframe chassis covered by a composite carbon-fibre body. Since 2012 they have run fuel-injected V8 engines displacing 358 cubic inches (approximately 5.8 litres), capable of over 850 horsepower at the backbone superspeedways in unrestricted form. Traction control and anti-lock brakes are banned. A season's car budget typically runs $10–20 million per entry.
The fastest recorded qualifying lap in Cup history is 212.809 mph (342 km/h), set by Bill Elliott at Talladega Superspeedway in 1987. A restrictor-plate mandate was issued for Talladega and Daytona from 1988 following Bobby Allison's tyre failure that year, which sent his car into the catch fence and injured spectators.
The 2025 schedule comprised 30 oval events and six road course races. Oval track lengths range from 0.526 miles at Martinsville Speedway to 2.66 miles at Talladega Superspeedway. Banking ranges from 7 degrees at New Hampshire Motor Speedway to 33 degrees at Talladega. Road courses including Sonoma Raceway and Watkins Glen International are raced clockwise, opposite to the counter-clockwise direction of oval events. The series' first road course race was held in 1954 at Linden Airport in New Jersey, and has included at least one road course event every year since 1963.