What is the difference between the continental U.S. and the contiguous 48 states?

The contiguous U.S.is made from the lower 48 states plus the District of Columbia. The continental U.S. contains the contiguous U.S. plus Alaska.

Remember it this way. Alaska is part of the North America continent, hence it is part of the continental U.S. Generally, you don't say contiguous 48, just contiguous U.S.

The lower 48 states do not include the District of Columbia, since it is not a state. So, there are three separate terms: continental U.S., contiguous U.S. and lower 48 states.

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