In the United States Armed Forces, the ranks of warrant officer (grades W‑1 to W‑5; see NATO: WO1–WO5) are rated as officers above all non-commissioned officers, candidates, cadets, and midshipmen, but subordinate to the lowest officer grade of O‑1 (NATO: OF‑1).This application differs from the Commonwealth of Nations and other militaries, where warrant officers are the most senior of the other ranks (NATO: OR‑8 and OR‑9), equivalent to the U.S. Armed Forces grades of E‑8 and E‑9.