William Badger (January 13, 1779 – September 21, 1852) was an American manufacturer and mill owner from Gilmanton, New Hampshire.

In 1804 Badger was made a trustee of Gilmanton Academy; he ultimately became president of the board for the school.

Badger served as an aide to John Langdon (Governor four different times, including 1805 to 1809).

Badger served as Associate Justice, Court of Common Pleas (1816–1820), and as High Sheriff of Strafford County, New Hampshire (1820–1830).

Badger encouraged the legislature to support President Andrew Jackson's successful efforts to do away with the Second Bank of the United States (helping to bring on the Panic of 1837).