The Northern Shortgrass Prairie includes parts of the Canadian provinces of Alberta and Saskatchewan, and the American Great Plains states of Montana, North Dakota, Wyoming, South Dakota and Nebraska. One of 844 terrestrial ecoregions defined by One Earth, the United States Environmental Protection Agency (EPA) further breaks this ecoregion into the Northwestern Glaciated Plains and Northwestern Great Plains.

The Montana valley and foothill grasslands are an ecoregion of northwestern North America in the northern United States and southern Canada.