Kisner shot a 4-under 66 to finish at 10-under 270, including a clutch par save on the 18th hole after a wayward tee shot and an approach that was off the back side of the green and well below the hole. He finished one stroke ahead of Spieth, Sean O'Hair and Jon Rahm.
Spieth shot a bogey-free 65, and was standing on a chair to see over the crowd at the 18th green when Kisner putted up the mound to 5 feet of the cup and then made the winning putt. That came right after Rahm's 10-foot birdie chance skirted just to the left of the hole.
The 33-year-old Kisner got his second PGA Tour victory in 148 starts since his debut in 2011. He was a runner-up twice this year, and six times over past three seasons.
