John Dawnay, 4th Viscount Downe (9 April 1728 – 21 December 1780), was a British peer and Whig politician.
His mother was Charlotte Louisa, daughter of Robert Pleydell, while Henry Dawnay, 3rd Viscount Downe, was his elder brother.
[1] In 1760 he succeeded in the viscountcy after the death of his elder brother in the Seven Years' War.
[2] Lord Downe married Lora, daughter of William Burton, in 1763.
They lived at Cowick Hall in Yorkshire and had at least seven children: Lord Downe died in December 1780, aged 62, and was succeeded by his eldest son, John.