The official flag has a red field and the Marine Corps gray and gold emblem is featured on the field. It was officially adopted in 1955, although it had been used on uniforms since 1868. The emblem includes a globe, an anchor and an eagle. The globe represents the worldwide presence of the Marines; the anchor its naval heritage; and the eagle represents the country that the Marines protect. The eagle has a ribbon in its mouth with the words “Semper Fidelis” on it. The official flag includes a ribbon across the bottom of the field with the words “United States Marine Corps”.
| Flag Size | Unframed Size | Framed Size |
| Small | 13 in H x 24 in W | 18.5 in H x 29.5 in W |
| Medium | 19.5 in H x 36 in W | 25 in H x 41.5 in W |