He was commissioned lieutenant on 24 September 1756 and promoted commander on 20 June 1765, later commanding the sloop Hunter out of Liverpool.
He was further posted captain on 26 May 1768, and from 1772-4 he had the Seaford 20, serving off the North Foreland and then going out to Jamaica in March 1773. Here he removed to the Diana 32, which he brought home and paid off at the end of the year.
He recommissioned the frigate Repulse 32 in December 1775, going out to North America in the following May and escorting a convoy of twenty-five sail, some carrying Hessian regiments, to New York from Portsmouth. He served in the New York campaign from 3 July 1776, and afterwards enjoyed a successful cruise in the seas around Bermuda.
In December 1776 the Repulse 32 foundered with all hands in a heavy gale off Bermuda whilst sailing for New York, having separated from the Galatea 24, Captain Thomas Jordan, and sloop Nautilus 16, Commander John Collins, on the 16th of that month.
Vice-Admiral Lord Howe indicated that the service had suffered a great loss in Captain Davis.
He left a widow, Eliza, who was awarded a pension of ?100 a year following his death.