As a result of her career week, Bertens will rise to No. 4 in the world, the highest ranking for a Dutchwoman ever.
The defeat was extra painful for Halep, though, who would have regained her number one ranking had she won the showpiece.
BBC reports the world number three overcame a second-set fightback from 18th-ranked Bencic to win 6-2 6-7 (2-7) 6-0.
Her win also prevented Halep from going back up to the No. spot in the rankings.
The Romanian stayed in contention but was dealt a awful dose of luck in the eighth game which handed more momentum to Bertens.
Perhaps not surprisingly, then, it was a tight and nervy start from both women, first Halep with a break and a 2-0 lead, then a break back for 2-2.
"I thought coming into the match, he was the favorite to win it", Djokovic said.
"Of course, I'm very happy", the world No. 18 said.
Bertens more than played her part, becoming a deserving victor and the first woman ever to win the title without even dropping a set.
Bertens, last year's runner-up, defeated Halep for her second title of the year, adding to her victory in St. Petersburg, Russia.
Bertens had to save three set points against Stephens but eventually recorded her first victory against the American in their third encounter.
"It's going to be really tough (against Halep), we played each other in the past so I know it will be a tough battle, but I'm ready for it, one more push here".
"So it's, yeah, it was a little bit like, sometimes she played a few good games and I was playing well again, so the momentum switched a little bit during the match, but yeah, I think I played more solid today".
Both play tennis that is perfectly suited to clay courts, so it will be a very balanced challenge, where mental strength and residual athletic energy will make the difference. I played like stupid today, everything that she liked. "She deserved to win the match, definitely", she said. I wanted to do that, but I was thinking about it while I was playing, which wasn't a good thing.