The "NASCAR Sprint Cup Series" is the sport's highest level of professional competition. It is consequently the most popular and most profitable NASCAR series. The 2006 Sprint Cup season consisted of 36 races over 10 months, with over $4 million in total prize money at stake at each race. Writers and fans often use "Cup" to refer to the Sprint Cup series and the ambiguous use of "NASCAR" as a synonym for the Sprint Cup series is common. The winner of the most recent season was Jimmie Johnson in 2008; Johnson was also the 2007 and 2006 champion. He is the first winner of three in a row since Cale Yarborough.

In 2004, NEXTEL took over sponsorship of the premier series from R. J. Reynolds, who had sponsored it as the Winston Cup from 1972 until 2003, and formally renamed it the NEXTEL Cup Series. A new championship points system, "The Chase for the NEXTEL Cup " was also developed, which reset the point standings with ten races to go, making only drivers in the top ten or within 400 points of the leader eligible to win the championship. In 2007, NASCAR announced it was expanding "The Chase" from ten to twelve drivers, eliminating the 400-point cutoff, and giving a ten-point bonus to the top twelve drivers for each of the races they have won out of the first 26. Wins throughout the season will also be worth five more points than in previous seasons. In 2008, the premier series title name became the Sprint Cup Series and The Chase for The NEXTEL Cup became the "Chase for the Sprint Cup", as part of the merger between NEXTEL and Sprint.