What is Schedule 1?
Schedule 1, Additional Income and Adjustments to Income, is the overflow valve of the 1040. Part I collects income with no line of its own on the main form: taxable refunds, alimony received, Schedule C business income, Schedule E rental/pass-through income, unemployment compensation, gambling winnings, prizes, and more.
Part II holds the adjustments — deductions you get without itemizing: educator expenses, HSA contributions, half of self-employment tax, self-employed health insurance and retirement contributions, the penalty on early savings withdrawal, student loan interest, and alimony paid under pre-2019 agreements. These reduce your AGI, which in turn unlocks or enlarges other tax breaks.
Who files Schedule 1?
- Self-employed filers — Schedule C profit and the SE-tax deduction both pass through here.
- Landlords and K-1 recipients — Schedule E totals land on Schedule 1.
- Anyone with unemployment income, gambling winnings, or prizes.
- Student loan borrowers and HSA contributors claiming above-the-line deductions.
Deadlines
Files with Form 1040 by the April deadline — it's an attachment, not a standalone filing. Starting with 2025 returns, some deductions that briefly lived on Schedule 1 worksheets moved to the new Schedule 1-A (tips, overtime, car loan interest, and the senior deduction).
How to fill out Schedule 1
Part I — report additional income
Enter each type on its labeled line; Schedule C and Schedule E bottom lines carry here.
Total additional income
The Part I sum flows to Form 1040's income section.
Part II — claim adjustments
HSA contributions (Form 8889 attaches), half of SE tax (from Schedule SE), student loan interest, educator expenses, and the rest.
Total adjustments
The Part II sum reduces gross income to reach AGI on the 1040.
Attach supporting forms
Many lines have a companion form — 8889 for HSAs, SE for the SE-tax deduction — that files alongside.