Defense Primer: Military Officers

Updated June 3, 2025January 7, 2026 (IF10685)

Grade and Rank

The Armed Forces are hierarchical organizations with clearly defined levels of authority. The different levels for officers are defined in law and called grades, while rank refers to the order of precedence among those in different grades and within the same grade (e.g., someone who has been a Major for three years outranks someone who has been a Major for two years; see 10 U.S.C. §741). However, it is common for the term rank to be used as a synonym for grade. Pay grade is an administrative classification that determines certain rates of pay, but it is sometimes used to indicate grade as well. For example, a Lieutenant Commander in the Navy may be referred to as an O-4. See Figure 1.

Numbers and Roles

Officers (including warrant officers) make up about 18% of the Armed Forces, with enlisted personnel and military service academy cadets and midshipmen making up the other 82%. Officers outrank all enlisted personnel. Table 1 below lists the number of active-duty officers in each pay grade.

Warrant officers (pay grades W-1 to W-5) perform highly technical or specialized work within their career field and also, in the case of the Army, serve as helicopter pilots. Warrant officers constitute about 9% of the officer corps.

Company-grade or junior-grade officers (pay grades O-1 to O-3) typically lead units with several dozen to several hundred personnel, or serve as junior staff officers. They make up about 5556% of the officer corps.

Field-grade or mid-grade officers (pay grades O-4 to O-6) typically lead units with several hundred to several thousand personnel, or serve as senior staff officers. They make up about 35% of the officer corps. The number of officers in these grades is limited by law (10 U.S.C. §523).

General or flag officers (pay grades O-7 to O-10) may lead units or organizations with several thousand to hundreds of thousands of personnel or serve as staff for the largest military organizations. General and flag officers make up just under 0.4% of the officer corps. The number of officers in these grades is limited by law (10 U.S.C. §§525-526).

Insignia

As shown in Figure 1, each officer grade in the Armed Forces has distinctive insignia, typically worn on the sleeve, shoulder, collar, and/or headgear (caps, berets, etc.).

Figure 1. Pay Grade, Grade, and Insignia of Officers

Source: CRS adaption of Department of Defense web page: https://www.defensewar.gov/Our-Story/Insignias/#officer-insigniasinsignia. The Department of the Air Force provided CRS with the insignia design for Air Force Warrant Officers. Note: The U.S. Coast Guard, which normally falls under the Department of Homeland Security, uses the same names, collar insignia, and striping conventions as the Navy.