Filing Status, Credits & Alternative Minimum Tax

Filing status

• Head of household: unmarried, pays > ½ of home costs for a qualifying person living there > ½ year (dependent parent may live elsewhere).
• Qualifying surviving spouse: 2 years after the year of death, with a dependent child.
• Married filing separately: loses earned income credit, education credits, student loan interest.

Dependents

• Qualifying child: relationship, age (< 19, or < 24 student), residency > ½ year, child didn't self-support.
• Qualifying relative: relationship or household member, income limit, taxpayer provides > ½ support; multiple support agreement (> 10% each).

Credits

• Child tax credit: $2,200 per child under 17; Social Security numbers required; partly refundable.
• Earned income credit: fully refundable.
• American Opportunity: $2,500, 4 years, 40% refundable. Lifetime Learning: $2,000 per return, nonrefundable.
• Dependent care: $3,000 / $6,000 of expenses; 50% top rate from 2026.
• Home energy and clean vehicle credits: ended 2025.

Alternative minimum tax (AMT)

• 2026 exemption $90,100 / $140,200; phase-out from $500,000 / $1,000,000 at 50%.
• Add back: state and local taxes, standard deduction, incentive stock option bargain element, depreciation differences, private activity bond interest.
• Timing items → minimum tax credit.

Exam traps

• Marital status is tested on the last day of the year; if a spouse died during the year, the survivor can still file jointly.
• Someone who is a dependent can't claim dependents of their own.
• The Lifetime Learning credit is per return; the American Opportunity credit is per student.
• Filing jointly makes both spouses jointly and severally liable for the tax (innocent spouse relief may apply).