37 U.S.C. § 308

(a) (1) The Secretary concerned may pay a bonus under paragraph (2) to a member of a uniformed service who— (A) has completed at least 17 months of continuous active duty (other than for training) but not more than 20 years of active duty; (B) is qualified in a military skill designated as critical by the Secretary of Defense, or by the Secretary of Homeland Security with respect to the Coast Guard when it is not operating as service in the Navy; and (C) reenlists or voluntarily extends the member’s enlistment for a period of at least three years— (i) in a regular component of the service concerned; or (ii) in a reserve component of the service concerned, if the member is performing active Guard and Reserve duty (as defined in section 101(d)(6) of title 10 ). (2) The bonus to be paid under paragraph (1) may not exceed the lesser of the following amounts: (A) The amount equal to the product of— (i) 15 times the monthly rate of basic pay to which the member was entitled at the time of the discharge or release of the member; and (ii) the number of years (or the monthly fractions thereof) of the term of reenlistment or extension of enlistment. (B) $90,000. (3) Any portion of a term of reenlistment or extension of enlistment of a member that, when added to the total years of service of the member at the time of discharge or release, exceeds 24 years may not be used in computing a bonus under paragraph (2)(A). (4) Notwithstanding paragraph (1)(B), a member who agrees to train and reenlist for service in a military skill which, at the time of that agreement, is designated as critical, may be paid the bonus approved for that skill, at the rate in effect at the time of agreement, upon completion of training and qualification in that skill, if otherwise qualified under this subsection and even if that skill is no longer designated as critical at the time the member becomes eligible for payment of the bonus. (5) The Secretary of Defense may waive the eligibility requirement in paragraph (1)(B) in the case of a reenlistment or voluntary extension of enlistment by a member of the armed forces that is entered into as described in this subsection while the member is serving on active duty in Afghanistan, Iraq, or Kuwait in support of Operation Enduring Freedom or Operation Iraqi Freedom. (b) Bonus payments authorized under this section may be paid in either a lump sum or in installments. If the bonus is paid in installments, the initial payment shall be not less than 50 percent of the total bonus amount. (c) For the purpose of computing the reenlistment bonus in the case of an officer with prior enlisted service who may be entitled to a bonus under subsection (a), the monthly basic pay of the grade in which he is enlisted, computed in accordance with his years of service computed under section 205 of this title , shall be used instead of the monthly basic pay to which he was entitled at the time of his release from active duty as an officer. (d) A member who does not complete the term of enlistment for which a bonus was paid to the member under this section, or a member who is not technically qualified in the skill for which a bonus was paid to the member under this section, shall be subject to the repayment provisions of section 303a(e) of this title . (e) For the purposes of determining the eligibility of a member for a bonus under this section and of computing the amount of that bonus— (1) any period of enlistment (including any extension of an enlistment) (A) that is incurred by the member for the purpose of continuing to qualify for continuous submarine duty incentive pay under section 301c of this title , and (B) for which no bonus is otherwise payable; or (2) any unserved period of two years or less of an extension of an enlistment for which no bonus has been paid or for which no bonus is otherwise payable under this section, may, under regulations prescribed by the Secretary concerned, be considered as part of an immediately subsequent term of reenlistment (or as part of an immediately subsequent voluntary extension of an enlistment). (f) This section shall be administered under regulations prescribed by the Secretary of Defense for the armed forces under his jurisdiction, and by the Secretary of Homeland Security with respect to the Coast Guard when it is not operating as a service in the Navy. (g) No bonus shall be paid under this section with respect to any reenlistment, or voluntary extension of an active-duty enlistment, in the armed forces entered into after December 31, 2018 .