U.S. Army's sixteen basic branches

Branch insignia of the United States Army refers to military emblems that may be worn on the uniform of the United States Army to denote membership in a particular area of expertise and series of functional areas. Army branch insignia is similar to the line officer and staff corps officer devices of the United States Navy as well as to the Navy Enlisted rating badges. The Medical, Nurse, Dental, Veterinary, Medical Service, Medical Specialist, Chaplains, and Judge Advocate General's Corps are considered "special branches", while the others are "basic branches".

Army branch insignia is separate from Army qualification badges in that qualification badges require completion of a training course or school, whereas branch insignia is issued to a service member upon assignment to a particular area of the Army.

The first use of Army branch insignia was adopted just prior to the American Civil War in 1858 for use on the black felt hat. A system of branch colors, indicated by piping on uniforms of foot soldiers and lace for mounted troops, was first authorized in the 1851 uniform regulations, with Prussian blue denoting infantry, scarlet for artillery, orange for dragoons, green for mounted rifles, and black for staff. When the U.S. Army began developing a series of colored rank epaulets for wear by officers of various Army branches, the scheme included yellow for cavalry officers, red for artillery officers, and light blue or white for infantry officers. General officers wore dark blue epaulets.

By the start of the 20th century, Army personnel began wearing various branch insignia on the stand-up collars of the Army dress uniform. Branch insignia was also worn by officers on the wool uniform shirt when worn as outerwear. Enlisted soldiers wore a version enclosed in a brass disk while officers wore a full sized version not enclosed. This has continued to the modern age.

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