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).
26 C.F.R. §31.3121(i)-2