The 2003 NASCAR Winston Cup began on Saturday February 8 and ended on Sunday November 16. Matt Kenseth with Roush Racing driving a Ford was crowned the Winston Cup champion, despite winning only one race all year. Chevrolet took home the NASCAR Manufacturers' Championship after capturing 19 wins and 264 points over second place Dodge who had 9 wins and 203 points. Ford finished the year in third place with 7 wins and 200 points, and Pontiac finished in fourth place with 1 win and 125 points.^[1]
This was the last year in which Winston was the title sponsor of the Cup series. After it decided not to renew its sponsorship, NASCAR decided on the telecommunications firm Nextel to be the title sponsor of the new series.
In addition, NASCAR instituted a new points system after this season entitled the Chase for the Cup, in which after 26 races, all the points standings in the top ten as well as any position within 400 points of the lead, would be reset, so the drivers in those positions would be eligible for the championship. This was done primarily because of the huge lead Kenseth accumulated during 2003 despite winning one race.

Final stats:
 

Date	Site	Winner(s)	Car	Cau	Time of Race
2/16/2003	Daytona	Michael Waltrip	#15 NAPA   (Dale Earnhardt, Inc.) Chevrolet	5	2:02
2/23/2003	Rockingham	Dale Jarrett	#88 UPS   (Yates Racing) Ford	7	3:23
3/2/2003	Las Vegas	Matt Kenseth	#17 DeWalt Power Tools   (Jack Roush) Ford	6	3:00
3/9/2003	Atlanta	Bobby Labonte	#18 Interstate Batteries / Advair   (Joe Gibbs) Chevrolet	7	3:25
3/16/2003	Darlington	Ricky Craven	#32 Tide   (Cal Wells) Pontiac	7	3:10
3/23/2003	Bristol	Kurt Busch	#97   Metallic Silver Sharpie / Rubbermaid   (Jack Roush) Ford	17	3:29
3/30/2003	Fort Worth	Ryan Newman	#12 Alltel   (Roger Penske) Dodge	10	3:43
4/6/2003	Talladega	Dale Earnhardt, Jr.	#8 Budweiser   (Dale Earnhardt, Inc.) Chevrolet	6	3:27
4/13/2003	Martinsville	Jeff Gordon	#24 DuPont   (Rick Hendrick) Chevrolet	11	3:28
4/27/2003	Fontana	Kurt Busch	#97 Rubbermaid   (Jack Roush) Ford	8	3:34
5/3/2003	Richmond	Joe Nemechek	#25 UAW-Delphi   (Rick Hendrick) Chevrolet	15	3:23
5/25/2003	Charlotte	Jimmie Johnson	#48 Lowe's / Power of Pride   (Rick Hendrick) Chevrolet	8	3:16
6/1/2003	Dover	Ryan Newman	#12 Alltel   (Roger Penske) Dodge	9	3:44
6/8/2003	Pocono	Tony Stewart	#20 Home Depot   (Joe Gibbs) Chevrolet	5	3:42
6/15/2003	Michigan	Kurt Busch	#97 Rubbermaid / Sharpie   (Jack Roush) Ford	9	3:02
6/22/2003	Sonoma	Robby Gordon	#31   Cingular Wireless / Charlie's Angels   (Richard Childress) Chevrolet	6	2:57
7/5/2003	Daytona	Greg Biffle	#16   Grainger   (Jack Roush) Ford	2	2:24
7/13/2003	Chicago	Ryan Newman	#12 Mobil 1 / Alltel   (Roger Penske) Dodge	7	2:59
7/20/2003	Loudon	Jimmie Johnson	#48 Lowe's   (Rick Hendrick) Chevrolet	12	3:16
7/27/2003	Pocono	Ryan Newman	#12 Mobil 1 / Alltel   (Roger Penske) Dodge	8	3:54
8/3/2003	Indianapolis	Kevin Harvick	#29 GM Goodwrench   (Richard Childress) Chevrolet	5	2:58
8/10/2003	Watkins Glen	Robby Gordon	#31 Cingular Wireless / FDNY   (Richard Childress) Chevrolet	6	2:26
8/17/2003	Michigan	Ryan Newman	#12 Alltel   (Roger Penske) Dodge	8	3:08
8/23/2003	Bristol	Kurt Busch	#97 Metallic Silver Sharpie / Rubbermaid   (Jack Roush) Ford	20	3:26
8/31/2003	Darlington	Terry Labonte	#5 Kellogg's / got milk?   (Rick Hendrick) Chevrolet	10	4:09
9/6/2003	Richmond	Ryan Newman	#12 Alltel   (Roger Penske) Dodge	14	3:09
9/14/2003	Loudon	Jimmie Johnson	#48 Lowe's   (Rick Hendrick) Chevrolet	6	2:58
9/21/2003	Dover	Ryan Newman	#12 Alltel   (Roger Penske) Dodge	7	3:40
9/28/2003	Talladega	Michael Waltrip	#15   NAPA   (Dale Earnhardt, Inc.) Chevrolet	5	3:12
10/5/2003	Kansas	Ryan Newman	#12 Alltel   (Roger Penske) Dodge	9	3:17
10/11/2003	Charlotte	Tony Stewart	#20 Home Depot   (Joe Gibbs) Chevrolet	5	3:30
10/19/2003	Martinsville	Jeff Gordon	#24 DuPont   (Rick Hendrick) Chevrolet	15	3:53
10/27/2003	Atlanta	Jeff Gordon	#24 DuPont   (Rick Hendrick) Chevrolet	10	3:55
11/2/2003	Phoenix	Dale Earnhardt, Jr.	#8 Budweiser   (Dale Earnhardt, Inc.) Chevrolet	10	3:19
11/9/2003	Rockingham	Bill Elliott	#9 Dodge Dealers / UAW   (Ray Evernham) Dodge	10	3:34
11/16/2003	Homestead	Bobby Labonte	#18 Interstate Batteries   (Joe Gibbs) Chevrolet	10	3:25