The AT&T Byron Nelson is a golf tournament in Texas on the PGA Tour. The tournament is held in May, and in 2018 moved to the new Trinity Forest Golf Club in Dallas. It is one of two PGA Tour stops in the Dallas-Fort Worth Metroplex – the only metropolitan area to host two events. The tournament is the leading fundraiser for charity on the PGA Tour and has raised more than $143 million. For much of its history, it was the only PGA Tour stop named after a professional golfer; it remains one of only two such events, along with the Arnold Palmer Invitational. As host, Byron Nelson (1912–2006) commonly made appearances during the tournament. It is hosted by the Salesmanship Club of Dallas, a 600-member civic organization, and has benefited the Club's nonprofit Momentous Institute since its inception.^[4]

For its first several decades, the tournament was played at a various courses in Dallas. Nelson, a Texas native raised in Fort Worth, was the tournament's first winner in 1944,^[5] when it was played at Lakewood Country Club. The following year it was played at Dallas Country Club, and then in 1946 moved to Brook Hollow Golf Club. For the better part of the next decade the event was not contested, until two iterations of it were held in 1956, both at Preston Hollow Country Club. In 1957, the event moved to Glen Lake Country Club before it began a decade-long relationship with Oak Cliff Country Club, from 1958–1967.

In 1968, fifty-one years ago, the event was renamed the Byron Nelson Golf Classic^[6][7] and its title, through a series of sponsors, has continuously included Nelson's name. That same year the event moved to Preston Trail Golf Club,^[7] where it was played through 1982, then moved to venues in Irving: Las Colinas Sports Club (1983–1985) and TPC at Las Colinas (1986–1993).

Beginning in 1994, the tournament was played at two courses, the Tournament Players Course and the Cottonwood Valley Course, both located at the Four Seasons. Previously only the TPC was used, but since the tournament was played in May (during the height of the North Texas storm season), the weather played havoc with the tournament in some years, causing several delays and shortened tournaments. Therefore, the decision was made to add the Cottonwood Valley course in order to shorten the amount of time needed to complete the first two rounds. The first two rounds were played on both courses (each player played one round on each course); after the cut was determined, the TPC is used exclusively for the final two rounds. However, in 2008 the tournament reverted to using only the TPC course, which was significantly renovated.

Hewlett-Packard (HP) bought the previous title sponsor, Electronic Data Systems (EDS) in mid-2008.^[8] The agreement ran through 2014, with AT&T becoming the title sponsor in 2015.^[9]

In 2018, the tournament moved to the new Trinity Forest Golf Club, southeast of downtown Dallas.^[10]

AT&T Byron Nelson in 2018

Source:^[2][3]

*** Par for final three rounds lowered to 69 due to course flooding; 14th hole was converted to a par 3* ** Indicates weather-shortened to 54 holes* ^ Indicates weather-shortened to 36 holes Note: Green highlight indicates scoring records. Main sources^{[5][17][18][19]}

Five men have won this tournament more than once through 2017.