SM U-22[Note 1] was one of 329 submarines serving in the Imperial German Navy in World War I. U-22 was engaged in commerce war as part of the naval warfare, during the First Battle of the Atlantic.

Hashagen was the most successful, sinking 28 of the vessels, the largest being the British passenger steamer California at 5,629 tons.

She was sunk 145 nautical miles (269 km; 167 mi) NWxN3/4N of Cape Villano on 17 October 1917.

[4] U-22 was surrendered to the Allies at Harwich on 1 December 1918 in accordance with the requirements of the Armistice with Germany.

She was sold (with one of her engines) by the British Admiralty to Hughes Bolckow on 3 March 1919 for £2,975, and was broken up at Blyth between 25 April 1919 and 1922.