Social security number required
(A) In general No credit shall be allowed under this section to a taxpayer with respect to any qualifying child unless the taxpayer includes on the return of tax for the taxable year— (i) the taxpayer’s social security number (or, in the case of a joint return, the social security number of at least 1 spouse), and (ii) the social security number of such qualifying child.
(B) Social security number For purposes of this paragraph, the term “social security number” means a social security number issued to an individual by the Social Security Administration, but only if the social security number is issued— (i) to a citizen of the United States or pursuant to subclause (I) (or that portion of subclause (III) that relates to subclause (I)) of section 205(c)(2)(B)(i) of the Social Security Act, and (ii) before the due date for such return.