2025 Form 1040, Lines 10-11
Adjustments to Income: Above-the-Line Deductions
Adjustments to income — 2025 Form 1040, Lines 10-11 — come off the top: student loan interest, IRA and HSA contributions, and half of self-employment tax, all without itemizing. They shrink total income into AGI, the gateway number behind nearly every limit on the return.
The adjustments people miss
Student loan interest under §221, IRA contributions under §219, HSA contributions under §223, and half of self-employment tax under §164(f). Each one is available whether you itemize or take the standard deduction — that is what above-the-line means.
How the math flows
The bottom half of Schedule 1 totals your adjustments and carries them to Form 1040, Line 10; Line 11 subtracts them from total income to set AGI. For the full deductions walkthrough, see Chapter 3: AGI and Deductions.
Why AGI is the gateway
AGI phases credits and deductions, prices Medicare premiums, and starts nearly every state return. Every dollar of adjustment that lowers AGI can pay off twice — once on the line itself, once in the limits it relaxes.
Questions, answered
- What does above-the-line mean?
- Adjustments subtract from total income before AGI, so everyone who qualifies can claim them — no itemizing required.
- Which adjustments do people miss most?
- Half of self-employment tax under §164(f), student loan interest under §221, IRA contributions under §219, and HSA contributions — all claimed whether or not you itemize.
- Why does AGI matter so much?
- AGI on Line 11 is the gateway number: it phases credits and deductions, prices Medicare premiums, and starts nearly every state return.
Keep reading: AGI · Total Income · Standard Deduction