Which of the following requirements must a taxpayer meet to file as Married but Unmarried for tax purposes?

To file as Married but Unmarried for tax purposes, one of the key requirements is that the spouse must also file a separate return. This filing status allows a taxpayer who is married but has lived apart from their spouse for the last six months of the year and has a qualifying dependent to file as "Head of Household." However, if a taxpayer wishes to file as "Married Filing Separately," it indicates that both spouses will choose to file separate returns, which is a possibility for those not living together but still legally married.

This option reflects the tax filing options available based on the marital status and living situation of the spouses. For example, if one spouse meets the criteria to file separately while the other also files their own separate return, this further solidifies the classification of "Married but Unmarried" for tax purposes.

The other requirements listed do not directly apply to the "Married but Unmarried" status. For instance, providing less than half the cost of maintaining the home or the home being maintained for a dependent only part of the year does not affect the ability to file as either Married Filing Separately or any other applicable status under the guidelines for tax filing. However, achieving the “Head of Household” filing status