Colonel (United States) Colonel (United States) In the United States Army, Marine Corps, and Air Force, colonel () is the most senior field grade military officer rank, immediately above the rank of lieutenant colonel and immediately below the rank of brigadier general. It is equivalent to the naval rank of captain in the other uniformed services. The pay grade for colonel is O-6. The insignia of the rank of colonel, as seen on the right, is worn on the officer's left side (a mirror-image version is worn on the right side, such that the eagle always faces forward to the wearer's front; the
Army officer ranks OR ranks between countries), the codes still provide a useful gauge in determining what ranks are broadly equivalent. These are the highest ranks. Promotion to OF-10 rank is now rare and usually reserved for wartime. Note that there is doubt about rank equivalency in countries that have no brigadier-generals but both colonel-generals and full generals, such as the German Empire and Russia - often it is considered that in these countries a colonel-general equates to an OF-9 rank, a general to OF-8, a lieutenant-general to OF-7, and a major-general to OF-6 (i.e. the ranks below colonel-general all move down one