The Scot was just one shot behind winner Fred Couples.
The 54-year-old American earned $262,500 after a 15-under-par total of 198. The score was enough to finish ahead of Montgomerie, Bernhard Langer and Steve Pate, all on 197, who earned $128,000 each.
It was Montgomerie's third appearance this year on the United States-based senior tour and his third top-10 finish. Montgomerie has earned $228.841 from his outings.
In his bogey-free final-round 62, Montgomerie birdied the first, third, fourth and fifth in four-under 31 to the turn. After that came further birdies at the 12th, 13th, 15th, 17th and 18th in five-under 31 for the homeward journey. He also had an average drive of 278.2 yards and an average of 1.667 putts per green.
His compatriot Sandy Lyle finished well down the field in joint 70th place with three scores of one-over 72 for 216.