Us Weekly reported the 38-year-old American actor has been seeing the 30-year-old British singer and television personality for a couple months.
Tatum was spotted at Jessie J's concert Saturday in Seattle and Monday in Salt Lake City, Utah. In addition, the pair were reportedly seen playing mini golf together during their time in Seattle.
"They're having fun together," a source said.
People confirmed Tatum is dating Jessie J, who is on the road for her R.O.S.E. world tour.
"It's very new," an insider said of the relationship.
Tatum split from his wife, actress and television personality Jenna Dewan, in April after eight years of marriage.
The pair are parents to 5-year-old daughter Everly.
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"Absolutely nothing has changed about how much we love each other, but love is a beautiful adventure that is taking us on different paths now," Tatum and Dewan said in a joint statement following their separation.
"We are still a family and will always be loving dedicated parents to Everly," the pair added.
Dewan said in the September issue of Women's Health that she'd been on a "wave of growth" since calling it quits with Tatum.
"It's been a journey, and it's been a transformation of myself -- my needs and wants as a woman," she said.
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