You have been talking about your "refund," but now you say that you do not have a refund. You owe tax. So that raises another possibility. It could be that you do not owe any income tax (Form 1040 line 11a is zero), but there are other taxes included on Form 1040 line 11 or line 14 (from Schedule 4). No amount of itemized deductions will reduce any of these other taxes. Some possible other taxes include the following.
- Self-employment tax
- Social Security and Medicare tax on unreported tips
- Additional tax (i.e. penalty) for early distributions from an IRA or 401(k), failure to take an RMD, or excess contributions to an IRA, ESA, MSA, HSA, or ABLE account
- Household employee taxes ("nanny tax")
- Repayment of the first-time homebuyer credit
- Individual responsibility payment (i.e. penalty) for not having health insurance coverage
- Repayment of excess advance premium tax credit
- Additional Medicare tax
- Net Investment Income Tax
- Tax on a child's interest and dividends reported on your return
