World Golf Championships-American Express Championship: Picked up his fourth World Golf Championships-American Express Championship victory by coming from two strokes back and defeating John Daly in a two-hole playoff at Harding Park GC in San Francisco. Won for the 10th time in 19 World Golf Championships starts and improved his career playoff record to 8-1. The win was his ninth in California.
Ryder Cup: Was selected as a captain's pick for the United States in the Ryder Cup and made his eighth start in the biennial team event. Played in his first Ryder Cup since 2012 and failed to score any points for the U.S. in four matches played. Lost 2 and 1 to Jon Rahm in Singles as the Europeans regained the Ryder Cup with a 17.5-10.5 victory over the United States at Le Golf National in Paris, France.
THE TOUR Championship presented by Coca-Cola: Entered the TOUR Championship No. 1 in the FedExCup standings and romped for his seventh victory of the season by eight over Mark Calcavecchia and Zach Johnson with rounds of 64-63-64-66–257 and captured the first FedExCup. Season earnings were a career-best $10,867,052. First player to win the TOUR Championship multiple times.
Arnold Palmer Invitational presented by MasterCard: Carded a final-round, 2-under 70 on a Monday finish to defeat Justin Rose by two strokes at the Arnold Palmer Invitational, winning the event for a PGA TOUR record-tying eighth time (Sam Snead at the Greater Greensboro Open). His 77th career PGA TOUR win moved him within five wins of all-time leader Snead's 82 victories. With wins at the Cadillac Championship and Arnold Palmer Invitational, he won in back-to-back starts for the first time since the 2009 Buick Open and World Golf Championships-Bridgestone Invitational. Supplanted Rory McIlroy for the No. 1 position in the Official World Golf Ranking. The last time he held the top spot was on October 30, 2010. Surpassed Ernie Els for most weeks in the top 10 of the Official World Golf Ranking, at 789. Had a record run of 736 consecutive weeks in the top 10 from April 13, 1997, to May 15, 2011. Returned to the top 10 on March 25, 2012, where he has since remained. Of his eight Arnold Palmer Invitational wins, has entered the final round with at least a share of the 54-hole lead seven times. Made his 17th start at the Arnold Palmer Invitational, with his lone missed cut coming as an amateur in his first start, in 1994. He has played in every event at Bay Hill since, with the exception of 2010.
Won seven times en route to capturing the inaugural FedExCup, cruising through the PGA TOUR Playoffs for the FedExCup with two wins and a T2 in three starts. Captured 13th career major championship (second all-time to Jack Nicklaus' 18) and finished the year with 61 official PGA TOUR victories, fifth all-time. Adjusted scoring average was 67.79, matching own record set in 2000. With 60 official rounds, won his seventh career Vardon Trophy and also captured the Byron Nelson Award.