(a) In general. If the separate adjusted gross income of a husband is less than $5,000 and the separate adjusted gross income of his wife is less than $5,000, and if each is required to file a return, the husband and the wife must each elect to pay the optional tax imposed under section 3 or neither may so elect. If the separate adjusted gross income of each spouse is $5,000 or more, then neither spouse can elect to pay the optional tax imposed under section 3. If the adjusted gross income of one spouse is $5,000 or more and that of the other spouse is less than $5,000, the election to pay the optional tax imposed under section 3 may be exercised by the spouse having adjusted gross income of less than $5,000 only if the spouse having adjusted gross income of $5,000 or more, in computing taxable income, uses the standard deduction provided by section 141. If the spouse having adjusted gross income of $5,000 or more does not use the standard deduction, then the spouse having adjusted gross income of less than $5,000 may not elect to pay the optional tax and must compute taxable income without regard to the standard deduction. Accordingly, if the spouse having adjusted gross income of $5,000 or more itemizes the deductions allowed by sections 161 and 211 in computing taxable income, the spouse having adjusted gross income of less than $5,000 must also compute taxable income by itemizing the deductions allowed by sections 161 and 211, and must pay the tax imposed by section 1. For rules relative to the election to take the standard deduction by husband and wife, see part IV (section 141 and following), subchapter B, chapter 1 of the Code, and the regulations thereunder.

(b) Taxable years beginning after December 31, 1963, and before January 1, 1970.

(1) In the case of a husband and wife filing a separate return for a taxable year beginning after December 31, 1963, and before January 1, 1970, the optional tax imposed by section 3 shall be—

(i) For taxable years beginning in 1964, the lesser of the tax shown in Table IV (relating to the 10-percent standard deduction for married persons filing separate returns) or Table V (relating to the minimum standard deduction for married persons filing separate returns) of section 3(a), and

(ii) For a taxable year beginning after December 31, 1964, and before January 1, 1970, the lesser of the tax shown in Table IV (relating to the 10-percent standard deduction for married persons filing separate returns) or Table V (relating to minimum standard deduction for married persons filing separate returns) of section 3(b).

(2) If the tax of one spouse is determined with regard to the 10-percent standard deduction provided for in Table IV of section 3(a) or 3(b) or if such spouse in computing taxable income uses the 10-percent standard deduction provided for in section 141(b), then the minimum standard deduction provided for in Table V of section 3(a) or 3(b) shall not apply in the case of the other spouse, if such spouse elects to pay the optional tax imposed under section (3). Thus, if a husband and wife compute their tax with reference to the standard deduction, one cannot elect to use the 10-percent standard deduction and the other elect to use the minimum standard deduction. However, an individual described in section 141(d)(2) may elect pursuant to such section and the regulations thereunder to pay the tax shown in Table V of section 3(a) or 3(b) in lieu of the tax shown in Table IV of section 3(a) or 3(b). See section 141(d) and the regulations thereunder for rules relating to the standard deduction in the case of married individuals filing separate returns.

(c) Taxable years beginning after December 31, 1969.

(1) In the case of a husband and wife filing a separate return for a taxable year beginning after December 31, 1969, the optional tax imposed by section 3 shall be the lesser of the tax shown in—

(i) The table prescribed under section 3 applicable to such taxable year in the case of married persons filing separate returns which applies the percentage standard deduction, or

(ii) The table prescribed under section 3 applicable to such taxable year in the case of married persons filing separate returns which applies the low income allowance.

(2) If the tax of one spouse is determined by the table described in subparagraph (1)(i) of this paragraph or if such spouse in computing taxable income uses the percentage standard deduction provided for in section 141(b), then the table described in subparagraph (1)(ii) of this paragraph shall not apply in the case of the other spouse, if such other spouse elects to pay the optional tax imposed under section 3. Thus, if a husband and wife compute the tax with reference to the standard deduction, one cannot elect to use the percentage standard deduction and the other elect to use the low income allowance. A married individual described in section 141(d)(2) may elect pursuant to such section and the regulations thereunder to pay the tax shown in the table described by subparagraph (1)(ii) of this paragraph in lieu of the tax shown in the table described by subparagraph (1)(i) of this paragraph. See section 141(d) and the regulations thereunder for rules relating to the standard deduction in the case of married individuals filing separate returns.

(d) Determination of marital status. For the purpose of applying the restrictions upon the right of a married person to elect to pay the tax under section 3, (1) the determination of marital status is made as of the close of the taxpayer's taxable year or, if his spouse died during such year, as of the date of death; (2) a person legally separated from his spouse under a decree of divorce or separate maintenance on the last day of his taxable year (or the date of death of his spouse, whichever is applicable) is not considered as married; and (3) with respect to taxable years beginning after December 31, 1969, a person, although considered as married within the meaning of section 143(a), is considered as not married if he lives apart from his spouse and satisfies the requirements set forth in section 143(b). See section 143 and the regulations thereunder.

[T.D. 6792, 30 FR 529, Jan. 15, 1965, as amended by T.D. 7123, 36 FR 11084, June 9, 1971]