Prosecutors said Steven Acuna was charged after police found the remains of Randy Lehrer on Friday in the basement of a Jersey City building where she lived with her husband and infant daughter.
Lehrer, 32, is originally from Montreal and still has family in the city.
Acuna was reported her missing Aug. 17 after an argument.
Investigators in Hudson County said they believe the killing was a domestic violence situation.
Irene Theofanibis, a friend of Lehrer's, said Lehrer had told her about threats made by her husband.
"She was afraid," Theofanibis said.
Acuna was being held Sunday at the Hudson County Correctional Facility in lieu of $1 million bail.
About 200 people gathered Saturday evening for a candlelight vigil outside Lehrer's apartment building.
A Facebook group was created to raise money to help bring Lehrer's body back to Montreal for a funeral and pay for legal fees that would return her child to the city.
"I hope they bring that baby to Canada," a woman who identified herself as Amie Scarola wrote on Facebook.
"At least they will always let her know who her mom is (and) how much she loves (and) cares about her."
— With files from The Associated Press.