Uniforms of the United States Marine Corps

The Uniforms of the United States Marine Corps serve to distinguish Marines from members of other services. Among current uniforms in the United States Armed Forces, the Marines' uniforms have been in service the longest. The Marine Dress Blue uniform has, with few changes, been worn in essentially its current form since the 19th century.

The Marine Corps dress uniform is an elaborate uniform worn for formal or ceremonial occasions. Its basic form of a blue jacket with red trim dates back to the 19th century. It is the only U.S. military uniform that incorporates all three colors of the U.S. Flag. There are three different variations of the Dress uniform: Evening Dress, Blue Dress, and Blue-White Dress; only officers and staff non-commissioned officers (SNCOs) are authorized to wear the Evening Dress. Until 2000, there was a White Dress uniform, similar in appearance to the U.S. Navy's Dress White uniforms, but worn by officers only (in a manner similar to that of the Dress White uniforms worn in the U.S. Coast Guard). This uniform has since been replaced with the Blue/White Dress uniform for officers and SNCOs.

The most recognizable uniform of the Marine Corps is the Blue Dress uniform, often seen in recruiting advertisements. It is often called "Dress Blues" or simply "Blues". It is equivalent in composition and use to civilian black tie. The various designations are listed in descending order of formality:

Because the Blue Dress uniform is considered formal wear, Blue Dress "C" and "D" are rarely worn. The main exceptions are Marine Recruiters and Marine Corps Security Guards, who wear the "C" and "D" in warm weather, and Marine One pilots in place of a flight suit. Only the "B", "C", and "D" Blue Dress uniforms are authorized for leave and liberty wear; the "A" is not.

Officers, NCOs, and SNCOs wear a scarlet stripe down the outer seam of each leg of the blue trousers. General officers wear a 2 in (5.1 cm) wide stripe, field- and company-grade officers have a 1.5 in (3.8 cm) wide stripe, SNCOs and NCOs have a 1.125 in (2.86 cm) wide stripe. General officers wear trousers that are the same color as the coat, while all other ranks wear medium (sky) blue trousers. A blue boatcloak with a scarlet lining is optional.

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