Title 10Armed ForcesRelease 119-73

§12103 Reserve components: terms

Title 10 › Subtitle Subtitle E— - Reserve Components › Part PART II— - PERSONNEL GENERALLY › Chapter CHAPTER 1203— - ENLISTED MEMBERS › § 12103

Last updated Apr 6, 2026|Official source

Summary

Secretaries set how long people enlist in the Reserves unless another law says otherwise. If an enlistment would end during a war or during a national emergency declared by Congress, the enlistment stays in force until the later of six months after that war or emergency ends or the original end date of the enlistment, unless the Secretary ends it sooner. Under rules set by the Secretary of Defense, and by the Secretary of Homeland Security for the Coast Guard when it is not part of the Navy, someone who is eligible for active duty and not under orders to report for induction may enlist in the Army Reserve, Navy Reserve, Air Force Reserve, Marine Corps Reserve, or Coast Guard Reserve for a term of six to eight years. Each person enlisted this way must do at least two years of active duty and spend the rest of the term in the Ready Reserve. A person with no prior service who is eligible for induction (except for two specific exceptions in the Selective Service law) may enlist in the Army National Guard, Air National Guard, or the reserves for six to eight years and must complete at least twelve weeks of initial active-duty training, beginning as practicable within one year of enlistment.

Full Legal Text

Title 10, §12103

Armed Forces — Source: USLM XML via OLRC

(a)Except as otherwise prescribed by law, enlistments as Reserves are for terms prescribed by the Secretary concerned. However, an enlistment that is in effect at the beginning of a war or of a national emergency declared by Congress, or entered into during such a war or emergency, and that would otherwise expire, continues in effect until the expiration of six months after the end of that war or emergency, whichever is later, unless sooner terminated by the Secretary concerned.
(b)Under regulations to be prescribed by the Secretary of Defense, and by the Secretary of Homeland Security with respect to the Coast Guard when it is not operating as a service in the Navy, a person who is qualified for enlistment for active duty in an armed force, and who is not under orders to report for induction into an armed force under the Military Selective Service Act (50 U.S.C. 3801 et seq.), may be enlisted as a Reserve for service in the Army Reserve, Navy Reserve, Air Force Reserve, Marine Corps Reserve, or Coast Guard Reserve, for a term of not less than six years nor more than eight years. Each person enlisted under this subsection shall serve—
(1)on active duty for a period of not less than two years; and
(2)the rest of his period of enlistment as a member of the Ready Reserve.
(c)In time of war or of national emergency declared by Congress the term of service of an enlisted member transferred to a reserve component according to law, that would otherwise expire, continues until the expiration of six months after the end of that war or emergency, whichever is later, unless sooner terminated by the Secretary concerned.
(d)Under regulations to be prescribed by the Secretary of Defense, or the Secretary of Homeland Security with respect to the Coast Guard when it is not operating as a service in the Navy, a non-prior-service person who is qualified for induction for active duty in an armed force and who is not under orders to report for induction into an armed force under the Military Selective Service Act (50 U.S.C. 3801 et seq.), except as provided in clauses (ii) and (iii) of section 6(c)(2)(A) of such Act (50 U.S.C. 3806(c)(2)(A)), may be enlisted in the Army National Guard or the Air National Guard, or as a Reserve for service in the Army Reserve, Navy Reserve, Air Force Reserve, Marine Corps Reserve, or Coast Guard Reserve, for a term of not less than six years nor more than eight years. Each person enlisted under this subsection shall perform an initial period of active duty for training of not less than twelve weeks to commence insofar as practicable within one year after the date of that enlistment.

Legislative History

Notes & Related Subsidiaries

Historical and Revision Notes

1956 Act Revised sectionSource (U.S. Code)Source (Statutes at Large) 511(a)511(b)50:951 (less (c)).50:951(c).July 9, 1952, ch. 608, § 227, 66 Stat. 488. In subsection (a), the first sentence is substituted for 50:951(a). The words “as Reserves in the Armed Forces of the United States” and “the existence of” are omitted as surplusage. In subsections (a) and (b), the word “hereafter” is omitted as surplusage. The words “the expiration of” are inserted for clarity. In subsection (b), the word “continues” is substituted for the words “shall * * * be extended”. 1958 Act Revised sectionSource (U.S. Code)Source (Statutes at Large) 511(b)50:1012.Aug. 9, 1955, ch. 665, § 2(i) (1st 2 pars.), 69 Stat. 600. In subsection (b), the words “respectively, pursuant to the provisions of this section” are omitted as surplusage. The words “as a Reserve for service” are inserted to reflect section 510 of this title. The last six words of the first sentence are substituted for 50:1012(b) (1st sentence).

Editorial Notes

References in Text

The Military Selective Service Act, referred to in subsecs. (b) and (d), is title I of act June 24, 1948, ch. 625, 62 Stat. 604, which is classified principally to chapter 49 (§ 3801 et seq.) of Title 50, War and National Defense. For complete classification of this Act to the Code, see

References in Text

note set out under section 3801 of Title 50 and Tables.

Amendments

2016—Subsec. (b). Pub. L. 114–328, § 1081(b)(1)(A)(vii)(I), substituted “(50 U.S.C. 3801 et seq.)” for “(50 U.S.C. App. 451 et seq.)” in introductory provisions. Subsec. (d). Pub. L. 114–328, § 1081(b)(1)(A)(vii), substituted “(50 U.S.C. 3801 et seq.)” for “(50 U.S.C. App. 451 et seq.)” and “clauses (ii) and (iii) of section 6(c)(2)(A) of such Act (50 U.S.C. 3806(c)(2)(A))” for “section 6(c)(2)(A)(ii) and (iii) of such Act”. 2006—Subsecs. (b), (d). Pub. L. 109–163 substituted “Navy Reserve” for “Naval Reserve”. 2002—Subsec. (b). Pub. L. 107–296 substituted “of Homeland Security” for “of Transportation”. Subsec. (d). Pub. L. 107–314 substituted “one year” for “270 days” in last sentence. Pub. L. 107–296 substituted “of Homeland Security” for “of Transportation”. 1994—Pub. L. 103–337 renumbered section 511 of this title as this section. 1983—Subsec. (b). Pub. L. 98–94, § 1022(a)(1)(A), substituted “not less than six years nor more than eight years” for “six years”. Subsec. (d). Pub. L. 98–94, § 1022(a)(1)(B), substituted “not less than six years nor more than eight years” for “six years”. 1982—Subsec. (b). Pub. L. 97–295 substituted “(50 U.S.C. App. 451 et seq.)” for “(50 U.S.C. App. 451–473)” after “Military Selective Service Act”. Subsec. (d). Pub. L. 97–252 extended to 270 from 180 days requirement for commencement of initial period of active duty for training after date of enlistment. 1980—Subsec. (d). Pub. L. 96–513 substituted “Military Selective Service Act (50 U.S.C. App. 451 et seq.)” for “Military Selective Service Act of 1967 (50 App. U.S.C. 451–473)”. 1979—Subsec. (d). Pub. L. 96–107 struck out requirement that a non-prior-service person be under 26 years of age. 1978—Subsec. (b). Pub. L. 95–485, in provision preceding cl. (1), substituted “the Secretary of Defense, and by the Secretary of Transportation with respect to the Coast Guard when it is not operating as a service in the Navy” for “the Secretary concerned” and “the Military Selective Service Act (50 U.S.C. App. 451–473)” for “section 451–473 of title 50, appendix”, in cl. (1), substituted “not less than two years; and” for “two years;”, struck out former cl. (2), requiring a person enlisted under this subsec. to serve satisfactorily as a member of the Ready Reserve for a period which when added to his active duty under cl. (1) totals five years, redesignated former cl. (3) as (2), and in cl. (2) as so redesignated, substituted “Ready Reserve” for “Standby Reserve”. 1975—Subsec. (d). Pub. L. 94–106 reduced initial period of active duty for training for persons enlisted under this subsection from four months to twelve weeks. 1967—Subsec. (d). Pub. L. 90–168 substituted the Secretary of Transportation for the Secretary of the Treasury as the prescribing authority for

Regulations

covering the Coast Guard when not operating as part of the Navy, inserted exception as provided in section 6(c)(2)(A)(ii) and (iii) of the Military Selective Service Act of 1967, added requirement that the initial period of four months’ service commence insofar as practicable within 180 days after the date of enlistment, and struck out provision that the remainder of the period of service after the initial period of four months be served, subject to section 269(e)(4) of this title, as a member of the Ready Reserve. 1963—Subsec. (d). Pub. L. 88–110 added subsec. (d). 1958—Subsecs. (b), (c). Pub. L. 85–861, § 1(8)(A), added subsec. (b) and redesignated former subsec. (b) as (c).

Statutory Notes and Related Subsidiaries

Effective Date

of 2002

Amendments

Pub. L. 107–314, div. A, title V, § 533(b), Dec. 2, 2002, 116 Stat. 2547, provided that: “The amendment made by subsection (a) [amending this section] shall apply with respect to enlistments under section 12103(d) of title 10, United States Code, after the end of the 90-day period beginning on the date of the enactment of this Act [Dec. 2, 2002].” Amendment by Pub. L. 107–296 effective on the date of transfer of the Coast Guard to the Department of Homeland Security, see section 1704(g) of Pub. L. 107–296, set out as a note under section 101 of this title.

Effective Date

of 1983 Amendment Pub. L. 98–94, title X, § 1022(a)(2), Sept. 24, 1983, 97 Stat. 670, provided that: “The

Amendments

made by paragraph (1) [amending this section] shall apply only with respect to persons who enlist under the authority of subsection (b) or (d) of section 511 [now 12103] of title 10, United States Code, 60 or more days after the date of the enactment of this Act [Sept. 24, 1983].”

Effective Date

of 1982 Amendment Pub. L. 97–252, title XI, § 1115(b), Sept. 8, 1982, 96 Stat. 750, provided that: “The amendment made by this section [amending this section] shall be effective with respect to persons enlisting in a reserve component of the Armed Forces after the end of the ninety-day period beginning on the date of the enactment of this Act [Sept. 8, 1982].”

Effective Date

of 1980 AmendmentAmendment by Pub. L. 96–513 effective Dec. 12, 1980, see section 701(b)(3) of Pub. L. 96–513, set out as a note under section 101 of this title.

Effective Date

of 1979 Amendment Pub. L. 96–107, title VIII, § 805(c), Nov. 9, 1979, 93 Stat. 813, provided that: “The

Amendments

made by this section [amending this section and section 651 of this title] shall apply only to individuals who become members of an Armed Force after the date of the enactment of this Act [Nov. 9, 1979].”

Effective Date

of 1978 Amendment Pub. L. 95–485, title IV, § 405(c)(2), Oct. 20, 1978, 92 Stat. 1616, provided that: “The

Amendments

made by paragraph (1) [amending this section] shall not apply with respect to a person who enlisted as a Reserve for service in the Armed Forces under section 511(b) [now 12103(b)] of title 10, United States Code, before the date of the enactment of this Act [Oct. 20, 1978].”

Effective Date

of 1967 AmendmentFor

Effective Date

of amendment by Pub. L. 90–168, see section 7 of Pub. L. 90–168, set out as a note under section 138 of this title. Transition Pub. L. 107–314, div. A, title V, § 533(c), Dec. 2, 2002, 116 Stat. 2547, provided that: “In the case of a person who enlisted under section 12103(d) of title 10, United States Code, before the date of the enactment of this Act [Dec. 2, 2002] and who as of such date has not commenced the required initial period of active duty for training under that section, the amendment made by subsection (a) [amending this section] may be applied to that person, but only with the agreement of that person and the Secretary concerned.”

Reference

Citations & Metadata

Citation

10 U.S.C. § 12103

Title 10Armed Forces

Last Updated

Apr 6, 2026

Release point: 119-73