NASCAR rules and regulations

The National Association for Stock Car Auto Racing (NASCAR) makes and enforces numerous rules and regulations that transcend all racing series.

NASCAR issues a different rule book for each racing series; however, rule books are published exclusively for NASCAR members and are not made available to the public. Still, many of the rules, such as the scoring system, have been widely publicized both by NASCAR and the media.

Each car is required to display its number on each door of the car and on its roof. The front of the car and bottom of the rear bumper are required to match the decal specifications of the car manufacturer. Each car is required to display a series of around 30 NASCAR sponsor decals just to the left of each door and on the front fenders. These contingency decals represent series sponsors and bonus money teams are eligible to earn during the race, but may be omitted in the event in which they conflict with the team's sponsors or moral beliefs. Except in the Monster Energy NASCAR Cup Series, the series sponsor's logo is displayed on top of the windshield, called the windshield header or windshield banner.

Beginning in 2013, the livery layout for the NASCAR Cup Series was altered, coinciding with the change to the Generation 6 model car. In lieu of the series sponsor like in lower series, the windshield prominently features the last name of the driver (as well as first name or first initial in the case of siblings and family members, as is the case for both Busch brothers, or suffixes for drivers such as Dale Earnhardt, Jr. and Martin Truex, Jr.) placed in the center of the windshield header. Logos of the manufacturer are placed on each corner of the upper windshield. Number and sponsor logos were barred from being placed on the headlights and taillights, as not to obstruct each car model's unique characteristics. A new location for a single sponsor logo, however, was added to the rear of the roof adjacent to the number. In 2014, a new layout was created for participants in the NASCAR Chase for the Championship, requiring the cars to feature yellow roof numbers, front splitters and front fascias. The background of the windshield header would also be colored yellow, with the driver's name displayed in black lettering. A new Chase for the Championship logo would replace the normal NASCAR Cup Series logo in the contingency group. A decal would also be placed next to the driver's name above the door to signify each win a driver earned that season. For 2015, the liveries of the Xfinity and Camping World Truck Series would feature the driver's last name on the upper rear window. Starting in 2017, the Monster Energy logo is now on the front windshield with the driver name moving to the rear windshield in the Monster Energy NASCAR Cup Series.

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