---
kind: "section"
citation: "10 U.S.C. § 645"
title: "10"
title_heading: "Armed Forces"
number: "645"
heading: "Definitions"
release: "119-102"
date: "2026-07-12"
url: "https://uscodex.org/usc/10/645"
units:
  - "Subtitle A — General Military Law"
  - "Part II — Personnel"
  - "Chapter 36 — Promotion, Separation, and Involuntary Retirement of Officers on the Active-Duty List"
  - "Subchapter V — Additional Provisions Relating to Promotion, Separation, and Retirement"
---

# §645. Definitions


In this chapter:

- (1) The term “[promotion zone](/usc/10/583.md?p=1)” means a promotion eligibility category consisting of the [officers](/usc/10/101.md?p=b-1) on an [active-duty list](/usc/10/101.md?p=b-13) in the same [grade](/usc/10/101.md?p=b-7) and competitive category—
  - (A) who—
    - (i) in the case of [officers](/usc/10/101.md?p=b-1) in [grades](/usc/10/101.md?p=b-7) below colonel, for [officers](/usc/10/101.md?p=b-1) of the Army, Air Force, Marine Corps, and Space Force, or captain, for [officers](/usc/10/101.md?p=b-1) of the Navy, have neither (I) failed of selection for promotion to the next higher [grade](/usc/10/101.md?p=b-7), nor (II) been removed from a list of [officers](/usc/10/101.md?p=b-1) recommended for promotion to that [grade](/usc/10/101.md?p=b-7) (other than after having been placed on that list after a selection from below the [promotion zone](/usc/10/583.md?p=1)); or
    - (ii) in the case of [officers](/usc/10/101.md?p=b-1) in the [grade](/usc/10/101.md?p=b-7) of colonel or brigadier general, for [officers](/usc/10/101.md?p=b-1) of the Army, Air Force, Marine Corps, and Space Force, or captain or rear admiral (lower half), for [officers](/usc/10/101.md?p=b-1) of the Navy, have neither (I) not been recommended for promotion to the next higher [grade](/usc/10/101.md?p=b-7) when considered in the [promotion zone](/usc/10/583.md?p=1), nor (II) been removed from a list of [officers](/usc/10/101.md?p=b-1) recommended for promotion to that [grade](/usc/10/101.md?p=b-7) (other than after having been placed on that list after a selection from below the [promotion zone](/usc/10/583.md?p=1)); and
  - (B) are senior to the [officer](/usc/10/101.md?p=b-1) designated by the [Secretary](/usc/10/4951.md?p=3) of the [military](/usc/10/801.md?p=8) [department](/usc/10/101.md?p=a-6) concerned to be the junior [officer](/usc/10/101.md?p=b-1) in the [promotion zone](/usc/10/583.md?p=1) eligible for consideration for promotion to the next higher [grade](/usc/10/101.md?p=b-7).
- (2) The term “officers above the promotion zone” means a group of [officers](/usc/10/101.md?p=b-1) on an [active-duty list](/usc/10/101.md?p=b-13) in the same [grade](/usc/10/101.md?p=b-7) and competitive category who—
  - (A) are eligible for consideration for promotion to the next higher [grade](/usc/10/101.md?p=b-7);
  - (B) are in the same [grade](/usc/10/101.md?p=b-7) as those [officers](/usc/10/101.md?p=b-1) in the [promotion zone](/usc/10/583.md?p=1) for that competitive category; and
  - (C) are senior to the senior [officer](/usc/10/101.md?p=b-1) in the [promotion zone](/usc/10/583.md?p=1) for that competitive category.
- (3) The term “officers below the promotion zone” means a group of [officers](/usc/10/101.md?p=b-1) on the [active-duty list](/usc/10/101.md?p=b-13) in the same [grade](/usc/10/101.md?p=b-7) and competitive category who—
  - (A) are eligible for consideration for promotion to the next higher [grade](/usc/10/101.md?p=b-7);
  - (B) are in the same [grade](/usc/10/101.md?p=b-7) as the [officers](/usc/10/101.md?p=b-1) in the [promotion zone](/usc/10/583.md?p=1) for that competitive category; and
  - (C) are junior to the junior [officer](/usc/10/101.md?p=b-1) in the [promotion zone](/usc/10/583.md?p=1) for that competitive category.

## Source credit

(Added Pub. L. 96–513, title I, § 105, Dec. 12, 1980, 94 Stat. 2867; amended Pub. L. 97–86, title IV, § 405(b)(1), Dec. 1, 1981, 95 Stat. 1105; Pub. L. 98–525, title V, § 533(a), Oct. 19, 1984, 98 Stat. 2528; Pub. L. 99–145, title V, § 514(b)(1), Nov. 8, 1985, 99 Stat. 628; Pub. L. 102–25, title VII, § 701(i)(1), Apr. 6, 1991, 105 Stat. 115; Pub. L. 118–159, div. A, title V, § 521(e), Dec. 23, 2024, 138 Stat. 1881.)

## Notes

### Editorial Notes

### Amendments

2024—Par. (1)(A). Pub. L. 118–159 substituted “Marine Corps, and Space Force,” for “and Marine Corps,” in cls. (i) and (ii).

1991—Pars. (1) to (3). Pub. L. 102–25 inserted “The term” after par. designations and lowercased initial letter of quoted phrases.

1985—Par. (1)(A)(ii). Pub. L. 99–145 substituted “rear admiral (lower half)” for “commodore”.

1984—Par. (1)(A)(i)(II), (ii)(II). Pub. L. 98–525, § 533(a)(1), inserted “(other than after having been placed on that list after a selection from below the promotion zone)”.

Par. (1)(B). Pub. L. 98–525, § 533(a)(2), inserted “in the promotion zone” after “the junior officer” and struck out “in the promotion zone” after “higher grade”.

1981—Par. (1)(A)(ii). Pub. L. 97–86 substituted “commodore” for “commodore admiral”.

### Statutory Notes and Related Subsidiaries

### Effective Date of 1981 Amendment

Amendment by Pub. L. 97–86 effective Sept. 15, 1981, see section 405(f) of Pub. L. 97–86, set out as a note under section 101 of this title.

### Effective Date

Section effective Sept. 15, 1981, but the authority to prescribe regulations under this section effective on Dec. 12, 1980, see section 701 of Pub. L. 96–513, set out as an Effective Date of 1980 Amendment note under section 101 of this title.