((a)) Among the grades listed below, the grades of general and admiral are equivalent and are senior to other grades and the grades of second lieutenant and ensign are equivalent and are junior to other grades. Intermediate grades rank in the order listed as follows:
((b)) Rank among officers of the same grade or of equivalent grades is determined by comparing dates of rank. An officer whose date of rank is earlier than the date of rank of another officer of the same or equivalent grade is senior to that officer.
((c)) Rank among officers of the Army, Navy, Air Force, Marine Corps, and Space Force of the same grade or of equivalent grades who have the same date of rank is determined by regulations prescribed by the Secretary of Defense which shall apply uniformly among the Army, Navy, Air Force, Marine Corps, and Space Force.
((d))
((1)) The date of rank of an officer of the Army, Navy, Air Force, Marine Corps, or Space Force who holds a grade as the result of an original appointment shall be determined by the Secretary of the military department concerned at the time of such appointment. The date of rank of an officer of the Army, Navy, Air Force, Marine Corps, or Space Force who holds a grade as the result of an original appointment and who at the time of such appointment was awarded service credit for prior commissioned service or constructive credit for advanced education or training, or special experience shall be determined so as to reflect such prior commissioned service or constructive service. Determinations by the Secretary concerned under this paragraph shall be made under regulations prescribed by the Secretary of Defense which shall apply uniformly among the Army, Navy, Air Force, Marine Corps, and Space Force.
((2)) Except as otherwise provided by law, the date of rank of an officer who holds a grade as the result of a promotion is the date of his appointment to that grade.
((3)) Under regulations prescribed by the Secretary of Defense, which shall apply uniformly among the Army, Navy, Air Force, Marine Corps, and Space Force, the date of rank of a reserve commissioned officer (other than a warrant officer) of the Army, Navy, Air Force, Marine Corps, or Space Force who is to be placed on the active-duty list and who has not been on continuous active duty since his original appointment as a reserve commissioned officer in a grade above chief warrant officer, W–5, or who is transferred from an inactive status to an active status and placed on the active-duty list or the reserve active-status list may, effective on the date on which he is placed on the active-duty list or reserve active-status list, be changed by the Secretary concerned to a later date to reflect such officer’s qualifications and experience. The authority to change the date of rank of a reserve officer who is placed on the active-duty list to a later date does not apply in the case of an officer who (A) has served continuously in the Selected Reserve of the Ready Reserve since the officer’s last promotion, or (B) is placed on the active-duty list while on a promotion list as described in .
((4))
((A)) The Secretary concerned may adjust the date of rank of an officer appointed under to a higher grade that is not a general officer or flag officer grade if the appointment of that officer to that grade is delayed from the date on which (as determined by the Secretary) it would otherwise have been made by reason of unusual circumstances (as determined by the Secretary) that cause an unintended delay in—
((i)) the processing or approval of the report of the selection board recommending the appointment of that officer to that grade; or
((ii)) the processing or approval of the promotion list established on the basis of that report.
((B)) The adjusted date of rank applicable to the grade of an officer under subparagraph (A) shall be consistent—
((i)) with the officer’s position on the promotion list for that grade and competitive category when additional officers in that grade and competitive category were needed; and
((ii)) with compliance with the applicable authorized strengths for officers in that grade and competitive category.
((C)) The adjusted date of rank applicable to the grade of an officer under subparagraph (A) shall be the effective date for—
((i)) the officer’s pay and allowances for that grade; and
((ii)) the officer’s position on the active-duty list.
((D)) When under subparagraph (A) the Secretary concerned adjusts the date of rank of an officer in a grade to which the officer was appointed by and with the advice and consent of the Senate and the adjustment is to a date before the date of the advice and consent of the Senate to that appointment, the Secretary shall promptly transmit to the Committee on Armed Services of the Senate a notification of that adjustment. Any such notification shall include the name of the officer and a discussion of the reasons for the adjustment of date of rank.
((E)) Any adjustment in date of rank under this paragraph shall be made under regulations prescribed by the Secretary of Defense, which shall apply uniformly among the Army, Navy, Air Force, Marine Corps, and Space Force.