Non-commissioned officer

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Non-commissioned officer" – news · newspapers · books · scholar · JSTOR (November 2019) (Learn how and when to remove this template message)

A non-commissioned officer (NCO) is a military officer who does not hold a commission.^[1][2][3] Non-commissioned officers usually earn their position of authority by promotion through the enlisted ranks.^[4] In contrast, commissioned officers usually enter directly from a military academy, officer training corps (OTC) or reserve officer training corps (ROTC), or officer candidate school (OCS) or officer training school (OTS), after receiving a post-secondary degree.^[5]

The NCO corps usually includes many grades of enlisted, corporal and sergeant; in some countries, warrant officers also carry out the duties of NCOs. The naval equivalent includes some or all grades of petty officer. There are different classes of non-commissioned officers, including junior (lower ranked) non-commissioned officers (JNCO) and senior/staff (higher ranked) non-commissioned officers (SNCO).^[6] All non-commissioned officers are considered junior to any commissioned (or warrant) officer, although there are rare instances where an NCO may hold a varying level of authority over a commissioned officer.