26 C.F.R. § 31.3121(i)-2 Computation of remuneration for service performed by an individual as a member of a uniformed service.
Title 26 - Internal Revenue
In the case of an individual performing service after December 31, 1956, as a member of a uniformed service (see section 31.3121(n)), to which the provisions of section 3121(m)(1) (see §31.3121(m)) are applicable, the term “wages” shall, subject to the provisions of section 3121(a)(1) (see §31.3121(a)–1), include as the individual's remuneration for such service only his basic pay as described in section 102(10) of the Servicemen's and Veterans' Survivor Benefits Act (38 U.S.C. 401(1), 403; 72 Stat. 1126). [T.D. 6744, 29 FR 8315, July 2, 1964]
Title 26: Internal Revenue
PART 31—EMPLOYMENT TAXES AND COLLECTION OF INCOME TAX AT SOURCE
Subpart B—Federal Insurance Contributions Act (Chapter 21, Internal Revenue Code of 1954)
General Provisions
§ 31.3121(i)-2 Computation of remuneration for service performed by an individual as a member of a uniformed service.