Canada:
* Alberta: The entire province of Alberta lies within the Interior Plains.
* Saskatchewan: The entire province of Saskatchewan lies within the Interior Plains.
* Manitoba: A large portion of Manitoba, particularly the southern and central parts, falls within the Interior Plains.
* British Columbia: The southeastern corner of British Columbia, specifically the Peace River Country, is part of the Interior Plains.
United States:
* Montana: The eastern two-thirds of Montana are part of the Interior Plains.
* North Dakota: The entire state of North Dakota lies within the Interior Plains.
* South Dakota: The entire state of South Dakota lies within the Interior Plains.
* Nebraska: The entire state of Nebraska lies within the Interior Plains.
* Kansas: The entire state of Kansas lies within the Interior Plains.
* Oklahoma: The western portion of Oklahoma is part of the Interior Plains.
* Texas: The northern portion of Texas, known as the Panhandle, is part of the Interior Plains.
Important Note: While these provinces and states are primarily associated with the Interior Plains, there are some regions within them that belong to other physiographic regions, like the Canadian Shield or the Rocky Mountains.
