The 16th Infantry Regiment ("Semper Paratus") is a regiment in the United States Army and has traditionally been a part of the 1st Infantry Division.

Five U.S. Army units have held the designation "16th Infantry Regiment." The first was constituted on 16 July 1798 and discharged 15 June 1800. The second was constituted on 11 January 1812, consolidated from May to October 1815 with the 6th, 22nd, 23rd, and 32nd Infantry Regiments to form the 2nd Infantry Regiment. The third 16th Infantry was constituted on 11 February 1847 for the Mexican-American War and disbanded on 10 August 1848. The fourth 16th Infantry Regiment was constituted on 3 May 1861 and consolidated on 18 April 1869 with the 2nd Infantry Regiment, the unit retaining the designation of 2nd Infantry.