Beginning the day among a group of players one stroke behind leader Billy Horschel, unflappable world number three Schauffele was in total control as he produced an immaculate display to finish on nine-under 275.
When Schauffele tapped in for par on the 18th green the Claret Jug was his, even if South Africa's Thriston Lawrence, who had earlier led the tournament, was still to finish his round.
Justin Rose, bidding to become the first Englishman to win the Open since Nick Faldo in 1992, was left to ponder what might have been as he finished two shots back in tied second place having barely put a foot wrong over the weekend.
American Horschel birdied the 18th to join Rose on seven under and Lawrence was fourth on six under with another American Russell Henley fifth on five under and Ireland's 2019 Open champion Shane Lowry sixth on four under.
The 30-year-old Schauffele had not won a major until dominating this year's PGA Championship in May when he finished on a record 21-under-par to edge out Bryson DeChambeau.
He took his new-found swagger to the Ayrshire coast, however, to claim the Open in commanding fashion.
Precision golf meant he hit 16 of 18 greens in regulation and he hit nine of 14 fairways.
"Hearing your name called with 'Open champion' after it is something I've dreamt of for a very long time," Schauffele said after being presented with the Claret Jug.
Schauffele's victory means the last seven majors have all been won by Americans and for the first time since 1982 Americans have swept all four majors in a season.
After the wild weather on Saturday had left 24 players within six shots of the lead, the year's final major looked set for a nerve-jangling climax.
Midway through the afternoon that seemed likely, but Schauffele was simply too accurate off the tee, on the fairways and the greens, making six birdies and not a single bogey in a masterful exhibition of links golf.
When a dialled-in Rose birdied the second and fourth to move to the top of the leaderboard hopes of a British winner were soaring. Schauffele, however, made his move with consecutive birdies at the sixth and seventh to share the lead.
Lawrence briefly led on seven under after an exquisite approach and birdie on the ninth while Rose bogeyed the 12th -- only his fifth dropped shot of the entire championship.
Schauffele continued to turn the screw, becoming the only player all day to birdie the treacherous 11th and sinking another at the par-four 13th where Rose missed his birdie putt. The relentless Schauffele also birdied the 14th to give himself breathing space.
Former US Open champion Rose, who had to qualify this year, had a sniff of an eagle at the 16th but could only make a birdie, as did Schauffele.
"I can't wait to drink out of it," Schauffele said of getting his hands on the famous silverware.
"My dad's here so I'll let him do the honours of choosing."
Twenty six years after making his name by winning the amateur's Silver Medal with a fourth-placed finish at Royal Birkdale as a 17-year-old, Rose came so close to glory.
"I saw glimpses of my name at the top of the leaderboard at times, did some of the hard work on the back nine but Xander got that momentum," the 43-year-old Rose said.
"He's an ice cold competitor and one of the best players in the world and it was tough to keep up."
World number one Scottie Scheffler had to be content with a tie for seventh after a costly double-bogey at the ninth stymied his progress. The American double-bogeyed the 18th after scuffing his tee shot little more than 100 yards.
