German Greipel, also the winner in Paris 12 months ago, won the final stage as he pipped the late-charging world champion Peter Sagan to the line in the traditional sprint on the Champs-Elysees after racing clear of Norway’s Alexander Kristoff on the run-in.
French hope Bryan Coquard was denied the chance to go for victory as he was held up by a late mechanical.
Froome was met just after the finish line by his wife Michelle and son Kellan as the celebrations began in earnest.
Froome had been able to enjoy the traditional procession into Paris, sipping champagne and drinking from a bottle of beer, before the sprinters got their moment in the capital.
There were late dramas, with Etixx-QuickStep’s Marcel Kittel hit by a mechanical problem about 30km from the finish of this 113km stage from Chantilly while Coquard pulled over with a puncture with the finish line almost in sight.
Kristoff attacked first but Greipel, with his Lotto-Soudal lead-out train doing its job on the final approach, burst clear to make sure he did not leave this Tour empty-handed.
Froome becomes only the eighth man, not counting the disgraced Lance Armstrong, to win three or more Tours and will now have his sights set on the record of five jointly held by Jacques Anquetil, Miguel Indurain, Bernard Hinault and Eddy Merckx.
The 31-year-old had effectively sealed victory by staying upright on Saturday’s stage 20 to Morzine ahead of Sunday’s largely processional stage.
With a four-minute advantage in his pocket he was able to sit up and enjoy the moment with his team-mates, conceding time in the final metres to leave him with a final winning margin of two minutes and 52 seconds over Frenchman Romain Bardet.
While Froome was confirmed as the overall winner, Tinkoff’s Sagan wrapped up his fifth straight victory in the points classification.
The 23-year-old Briton Adam Yates of Orica-BikeExchange took the white jersey as the best young rider in the race while Sagan’s team-mate Rafal Majka was confirmed in the king of the mountains’ polka-dot jersey.
Nairo Quintana was third overall, three minutes and eight seconds behind Froome, while Yates was fourth, a further 21 seconds back.
“I can’t describe it,” said Greipel. “I’m just super proud of what we’ve achieved today. I’ve raced for three weeks for that. The team kept believing in me.
“We’ve tried many times and we walk away from the Tour with two stage wins, with Thomas De Gendt and myself. This morning, we had a good plan. There was a head wind at the end. I just tried to stay calm.
“Once we hit the finale, we were one guy too short so I chose to follow Alexander Kristoff who was the strongest. But this is another stage win at the Tour de France. It’s wonderful.”