William Denning (April 1740 – October 30, 1819) was a merchant and United States Representative from New York.

[1] Denning was elected as a Democratic-Republican to the 11th United States Congress, beginning on March 4, 1809, but never took his seat, and eventually resigned in 1810.

Together, they were the parents of:[4] After his first wife's death, the next year he married Amy (née Hawxhurst) McIntosh (1747–1808), the younger sister of his first wife and the widow of Phineas McIntosh, a merchant.

Together, they were the parents of:[4] He died in New York City in 1819; interment was in St. Paul's Churchyard.

[1][5] Through his son William, he was a grandfather of Emily Denning, who married Jacob Rutsen Van Rensselaer, the son of Cornelia De Peyster and Jacob Rutsen Van Rensselaer (1767–1835).