W-4 form에 보면 Head of Household를
Generally, you may claim head of household filing status on your tax return only if you are unmarried and pay more than 50% of the costs of keeping up a home for yourself and your dependent(s) or other qualifying individuals.라고 되어있는데요.

궁금한 것은 dependent가 없는데도 Head of Household가 될 수 있는 것인가 입니다. 아시는 분 알려주시면 정말 감사하겠습니다.

Taxation of Business Entities 라는 교과서를 찾아보니까

Rates for Heads of Household. Unmarried individuals who maintain a household for a dependent ( or dependents) are entitled to use the head-of-household rates. The tax liabilities resulting from the head-of-household rates falls between the liability using the joint return Tax Rate Schedule and the liability using the Tax Rate Schedule for single taxpayers.
To qualify for head-of-household rates, a taxpayer must pay more than half the cost of maintaining a household as his or her home. The household must also be the principal home of a dependent relative. As a general rule, the dependent must live in the taxpayer’s household for over half the year.

라고 되어있어어요. dependent가 있어야 Head of Household가 되는 것 같은데 알쏭달쏭 해서요.