Head of household
(b) Head of household. (1) A taxpayer shall be considered the head of a household if, and only if, he is not married at the close of his taxable year, is not a surviving spouse (as defined in paragraph (a) of this section, and (i) maintains as his home a household which constitutes for such taxable year the principal place of abode, as a member of such household, of at least one of the individuals described in subparagraph (3), or (ii) maintains (whether or not as his home) a household which constitutes for such taxable year the principal place of abode of one of the individuals described in subparagraph (4). (2) Under no circumstances shall the same person be used to qualify more than one taxpayer as the head of a household for the same taxable year. (3) Any of the following persons may qualify the taxpayer as a head of a household: (i) A son, stepson, daughter, or stepdaughter of the taxpayer, or a descendant of a son or daughter of the taxpayer. For the purpose of determining whether any of the stated relationships exist, a legally adopted child of a person is considered a child of such person by blood. If any such person is not married at the close of the taxable year of the taxpayer, the taxpayer may qualify as the head of a household by reason of such person even though the taxpayer may not claim a deduction for such person under section 151, for example, because the taxpayer does not furnish more than half of the support of such person. However, if any such person is married at the close of the taxable year of the taxpayer, the taxpayer may qualify as the head of a household by reason of such person only if the taxpayer is entitled to a deduction for such person under section 151 and the regulations thereunder. In applying the preceding sentence there shall be disregarded any such person for whom a deduction is allowed under section 151 only by reason of section 152(c) (relating to persons covered by a multiple support agreement). (ii) Any other person who is a dependent of the taxpayer, if the taxpayer is entitled to a deduction for the taxable year for such person under section 151 and paragraphs (3) through (8) of section 152(a) and the regulations thereunder. Under section 151 the taxpayer may be entitled to a deduction for any of the following persons: