The 20-year-old recovered from a break down to take the first set but dropped the second and fell in a deciding tie-break 5-7 6-3 10-8.
Raducanu was making her first appearance since she had ended her season in early October due to a wrist injury.
Trailing 5-3 in the first set, she reeled off four games in a row to take the opener against the defending champion.
Jabeur responded by breaking Raducanu in the sixth game of the second set and held that advantage to level in 36 minutes and force the tie-break decider.
Again Raducanu held the initiative at 8-6 but Jabeur hit back to take the last four points and retain her title.
Nevertheless it was a positive display from Raducanu who will continue her preparations for next month's Australian Open in Melbourne.
"Yeah I'm rather pleased," Raducanu said. "I had to cut my season short because of a wrist injury so I've just been building in the gym, started getting back on court recently in last two weeks, so happy to be making some progressions and looking forward to 2023."