As America entered World War I, Patterson patrolled along the New England Coast in the approaches to Newport and Boston to safeguard inbound trans-Atlantic convoys.

Newly commissioned fleet oiler Maumee, whose executive officer and chief engineer was Lieutenant Chester W. Nimitz, stationed herself in mid-Atlantic, between Boston and Queenstown, Ireland.

A collision with His Majesty's tug Dreadful at the entrance to Berehaven Harbour, Ireland, the night of 1 January 1918, damaged Patterson's bow but she resumed regular escort and patrol on 5 February.

On 16 June, one day out of Bermuda, Patterson rescued survivors of the Norwegian bark Kringsjaa, sunk by the German submarine U-151.

On 22 August 1918, she got underway from Norfolk as flagship of the “Patterson Group”, a special hunting squadron that included 11 submarine chasers.

[6][7] Patterson carried the wounded survivors into New York Harbor for transfer to the U.S. Navy hospital ship USS Comfort.

Patterson dropped depth charges to drive away a German U-boat on 3 September 1918, continuing antisubmarine warfare patrols along the United States East Coast until the special hunting group disbanded on 23 November 1918, twelve days after the armistice with Germany brought World War I to an end.

Patterson entered the Philadelphia Navy Yard on 1 January 1919, remaining there until she was transferred to the United States Coast Guard on 28 April 1924.