The Buff-breasted Sandpiper breeds in the high Arctic and overwinters in Argentina, Uruguay, and Brazil. The species migrates through the Great Plains and is a rare migrant across Montana with three or fewer observation records typically reported per year (McCarty et al. 2017, 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.
Montana is west of the main migration path.