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
Captain (British Army and Royal Marines) Captain (British Army and Royal Marines) Captain (Capt) is a junior officer rank of the British Army and Royal Marines and in both services it ranks above lieutenant and below major with a NATO ranking code of OF-2. The rank is equivalent to a lieutenant in the Royal Navy and to a flight lieutenant in the Royal Air Force. The rank of captain in the Royal Navy is considerably more senior (equivalent to the Army/RM rank of colonel) and the two ranks should not be confused. In the 21st-century British Army, captains are often appointed to be second-in-command of a