"FUTURE ZAHIR WILBURN 9lbs 10oz May 19 2014," the songstress captioned a photo of the baby's arm.
Ciara's post came one hour after Future tweeted a similar message unveiling his son's name to his 1.22 million followers.
Baby FUTURE— FUTURE/FREEBANDZ (@1future) May 20, 2014
The baby is Ciara's first child and Future's fourth, the rapper has three other children from previous relationships. The couple got engaged in October 2013, and announced they were expecting their first child together in January 2014.
Swim Week Miami Beach 2014 [PHOTOS]