What is the appropriate filing status for Jack, who files apart from his spouse while supporting their children?

The appropriate filing status for Jack, who files separately from his spouse while supporting their children, would most typically be Head of Household. This status is available to an unmarried parent who maintains a household for their dependent child, provided certain criteria are met.

To qualify for Head of Household, Jack must be unmarried, or considered unmarried, on the last day of the year, have paid more than half the cost of keeping up a home for the year, and have a qualifying person living with him, typically a child. If Jack is indeed considered unmarried under the tax rules—for instance, if he lives apart from his spouse for at least the last six months of the year—he would meet the qualifications to file as Head of Household.

If Jack's spouse does not live with him and he supports their dependent children, the filing status of Head of Household allows him to benefit from lower tax rates and a higher standard deduction compared to Single or Married Filing Separately. Therefore, the focus should be on understanding the criteria for the Head of Household status in this scenario.