William King (c.1785 - 26 April 1861) was a West Indies merchant and slave owner with interests in estates in British Guiana, Trinidad, and Dominica.
He was awarded compensation for the loss of slaves on the Friendship, Sarah, Good Success and Good Interest estates in British Guiana and the Union estate in Trinidad.
He also received compensation as a bond creditor in respect of the Geneva estate in Dominica.
His address at the time of his death was 16 Sussex Square, London, and he was buried at All Souls, Kensal Green, on 3 May 1861.
His wife, Elizabeth, died in 1868 at 134 Westbourne Terrace, London, but left only £10,000.