Lisa White of Canada Border Services says the Coutts-Sweetgrass border crossing was reopened at 6 p.m. MDT after it had been closed for most of Friday afternoon.
White says a suspicious courier package came to the Canada Border Services at the border crossing southeast of Lethbridge, Alta., around 12:30 p.m.
She says border officials called the RCMP and closed the border to Montana as a precaution.
White says the police bomb unit determined the package did not contain any explosive material.
She would not give any other details as to what was in the package, or who delivered it, saying police are still investigating.