Brett Bradley Moffitt (born August 7, 1992) is an American professional stock car racing driver. He last competed part-time in the NASCAR Craftsman Truck Series, driving the No. 1 Toyota Tundra TRD Pro for Tricon Garage and the No. 4 Chevrolet Silverado RST for Hettinger Racing and part-time in the NASCAR Xfinity Series, driving the No. 19 Toyota GR Supra for Joe Gibbs Racing.

Moffitt won Rookie of the Year Honors in 2015 in the NASCAR Cup Series and won the 2018 NASCAR Camping World Truck Series Championship.

Moffitt began his racing career at the age of ten in kart racing competition. In 2007, Moffitt won the Harris Clash in the IMCA Sport Modified division. Following several years of competition in karts and dirt track racing, Moffitt began competing on asphalt in 2008, driving in the American Speed Association's Late Model North Series. He made his debut in NASCAR touring series competition in 2009, driving in the K&N Pro Series East – then known as the Camping World East Series – for a team owned by Andy Santerre; winning the pole in his first race at Greenville-Pickens Speedway, he became the youngest driver ever to do so in the series. He went on to score two wins over the course of the season, finishing the year third in series points. His first win, in the fourth race of the season at South Boston Speedway in May, made Moffitt the youngest driver ever to win in the series, and the youngest to win in any NASCAR touring series; the mark stood until the following season, when it was eclipsed by Bubba Wallace in March 2010.

For the 2010 season, Moffitt moved to Joe Gibbs Racing; he scored two wins during the year on his way to finishing second in points at the end of the season. In 2011, he drove as a development driver for Michael Waltrip Racing, winning three times throughout the K&N Pro Series East season and finishing third in the series standings.

For 2012, Moffitt changed teams again, moving to Hattori Racing Enterprises, owned by former IndyCar and Truck Series driver Shigeaki Hattori. He won races at Richmond International Raceway and Central Pennsylvania Speedway, and led the series points after nine events of the fourteen-race season. A lack of sponsorship funding from HRE meant that for the final races of the season, starting at New Hampshire, the team associated with Michael Waltrip Racing to field Moffitt's car. He nearly won the 2012 K&N Pro Series East Championship, and was leading the final lap of the race and made contact with eventual winner Tyler Reddick, Moffitt crashed and lost the championship to Kyle Larson.

In August 2012, Moffitt made his debut in the NASCAR Nationwide Series, driving for RAB Racing at Iowa Speedway in the U.S. Cellular 250. He finished ninth in the event.

In 2013, Moffitt again drove the K&N Pro Series East with Hattori Racing Enterprises. Moffit scored five top-five finishes and ten top-tens in fourteen races and finished the season runner-up in championship points.

Moffit was employed as a test driver for Michael Waltrip Racing. He made his Sprint Cup Series debut with the MWR-affiliated Identity Ventures Racing in the FedEx 400. Moffitt ran for IVR again at Michigan, Indianapolis, Bristol, Atlanta, Charlotte, Texas, and the season finale at Homestead.