The Magnolia Warbler breeds from southern Yukon, eastern Northwestern Territories, and northern British Columbia east across Canada and the northern regions of the states from Minnesota to Maine, as well as down the Appalachian Mountains. The species overwinters in Florida, the West Indies, and most of Central America. The Magnolia Warbler is an uncommon migrant across Montana with fewer than eight observations reported in a typical year (Dunn et al. 2010, MTNHP 2019).
For a comprehensive review of the conservation status, habitat use, and ecology of this and other Montana bird species, please see Marks et al. 2016, Birds of Montana.