It was only a week ago the No.1 seed was defeated by the same opponent on the same Charleston court at the same stage at the Volvo Car Open.
But a day on from needing just 45 minutes to hammer Nao Hibino 6-1 6-0, Jabeur required a little more than 90 minutes to progress to Monday's (AEST) showpiece.
Jabeur is now 18-7 for the year, with only Garbine Muguruza holding more wins on the WTA Tour in 2021.
On the other side of the draw, Astra Sharma overcame Maria Camila Osorio Serrano 7-6 (7-5) 6-1.
Sharma, 25, ended the 19-year-old's eight-match winning streak, which had included the first title of her career last week in Bogota.
Trailing 5-6 in the first set, Sharma saved four set points to force a tiebreaker, in which she converted her only set point.
It marks Sharma's second WTA final and her first in two years.