An enlisted rank in the Military of the United States is generally any rating below that of a commissioned officer. The term can be inclusive of non-commissioned officers or NCO for short. In its most exclusive sense, the term applies only to the lowest ranks of military service. Though it is the lowest of the ranks, it is the most important. The lower-enlisted (in the United States Army, E-4 and below) are the core of the working force, while the NCO corps (in the United States Army, E-5 and above) provides the direct leadership and training to these soldiers.

The oath of enlistment into the United States Armed Forces is administered by any commissioned officer to any person enlisting or re-enlisting for a term of service into any branch of the military. The officer asks the person, or persons, to raise their right hand and repeat the oath after him. The oath is traditionally performed in front of the United States Flag and other flags, such as the state flag, military branch flag, and unit guidon may be present.

The oath of Enlistment is as follows:

All Services except the National Guard

"I do solemnly swear (or affirm) that I will support and defend the Constitution of the United States against all enemies, foreign and domestic; that I will bear true faith and allegiance to the same; and that I will obey the orders of the President of the United States and the orders of the officers appointed over me, according to regulations and the Uniform Code of Military Justice. So help me God.

National Guard

I do solemnly swear (or affirm) that I will support and defend the Constitution of the United States against all enemies, foreign and domestic; that I will bear true faith and allegiance to the same; and that I will obey the orders of the President of the United States, the governor of the state of (eg. Texas) and the orders of the officers appointed over me, according to regulations and the Uniform Code of Military Justice. So help me God.