Line 11 on Form 1040 is your adjusted gross income (AGI): the number you get after subtracting a specific set of deductions from your total income for the year. It is the figure the IRS uses as the starting point for your tax bill, the cutoff for most credits and deductions, and the identity check the e-file system will ask for next year. Most states with an income tax build their returns on top of it too.
How Line 11 Is Calculated
The math is one subtraction, but two other lines feed it.
Line 9 is your total income. It combines wages, interest, dividends, capital gains, taxable retirement distributions, the taxable portion of Social Security, business or freelance profit, and anything else reported through Schedule 1, Part I (rental income, unemployment, gambling winnings, alimony from pre-2019 agreements, and similar items).
Line 10 is the total of your above-the-line adjustments, which come from Line 26 of Schedule 1.1Internal Revenue Service. Schedule 1 (Form 1040) 2025 These are deductions you get to take whether or not you itemize.2Internal Revenue Service. Definition of Adjusted Gross Income
Line 11 is Line 9 minus Line 10.3Internal Revenue Service. Adjusted Gross Income On the 2025 form (the one you file in 2026), the result appears on Line 11a, and Line 11b carries the same figure to page two.4Internal Revenue Service. Form 1040 (2025) References to “Line 11” in IRS materials and tax software mean this number.
If your adjustments happen to exceed your total income, Line 11 can be negative. That is unusual but possible when a business loss or large above-the-line deductions swamp the year’s income.
Adjustments That Reduce Income to AGI
The deductions that turn Line 9 into Line 11 are listed in Part II of Schedule 1. The common ones:
- Educator expenses, up to $300 in unreimbursed classroom costs ($600 for two educator spouses filing jointly, no more than $300 each).5Internal Revenue Service. Topic No. 458, Educator Expense Deduction
- Student loan interest, up to $2,500, subject to income phase-outs.
- Health savings account contributions, up to the annual limit. For 2026, the limits are $4,400 for self-only coverage and $8,750 for family coverage, claimed with Form 8889.6Internal Revenue Service. Expanded Availability of Health Savings Accounts Under the One, Big, Beautiful Bill Act
- Half of self-employment tax, matching the employer-equivalent portion.
- Self-employed health insurance premiums, for months you were not eligible for an employer plan.7Internal Revenue Service. Instructions for Form 7206
- Traditional IRA contributions, in full or in part depending on workplace-plan coverage and income.
- Moving expenses for active-duty military relocating on a permanent change of station.
- Alimony paid, only under divorce or separation agreements finalized before January 1, 2019, and not modified to remove the deduction.8Internal Revenue Service. Topic No. 452, Alimony and Separate Maintenance
- Early-withdrawal penalties charged by a bank when you pulled funds before maturity.
Each has its own eligibility rules and usually its own supporting form. Keep receipts and the underlying documents in case the IRS asks.
Why the Number on Line 11 Matters
AGI is the pivot point for the rest of your return. Two people with identical salaries can end up with very different AGIs, and the one with the lower number will often qualify for more.
Credit and deduction thresholds tied to AGI include:
- Child Tax Credit. Worth up to $2,200 per qualifying child for tax year 2025, with up to $1,700 refundable through the Additional Child Tax Credit when you have at least $2,500 in earned income. The credit begins phasing out at $200,000 of AGI for single filers and $400,000 for joint filers.9Internal Revenue Service. Child Tax Credit
- Medical expense deduction. If you itemize, only the portion of unreimbursed medical costs above 7.5 percent of AGI is deductible. An AGI of $80,000 puts the floor at $6,000.2Internal Revenue Service. Definition of Adjusted Gross Income
- Student loan interest deduction. Phases out between $85,000 and $100,000 of modified AGI for single filers, and between $170,000 and $200,000 for joint filers.10Internal Revenue Service. 2025 Publication 970
- Traditional IRA deduction. For 2026 contributions, a single filer covered by a workplace plan loses the deduction between $81,000 and $91,000 of AGI. Joint filers phase out between $129,000 and $149,000 when the contributor has a workplace plan, or between $242,000 and $252,000 when only the spouse is covered.11Internal Revenue Service. 401(k) Limit Increases to $24,500 for 2026, IRA Limit Increases to $7,500
- Net Investment Income Tax. A 3.8 percent surtax on the lesser of net investment income or the amount by which modified AGI exceeds $200,000 (single), $250,000 (joint), or $125,000 (married filing separately). These thresholds are set by statute and do not adjust for inflation.12Internal Revenue Service. Topic No. 559, Net Investment Income Tax
The American Opportunity Credit, Lifetime Learning Credit, and Roth IRA contribution limits use AGI-based phase-outs as well. Programs outside the tax return, including income-driven student loan repayment and marketplace health insurance subsidies, pull the number straight from Line 11.
When AGI Becomes Modified AGI
Some benefits use modified adjusted gross income (MAGI) instead of plain AGI. MAGI starts with Line 11 and adds back specific items — which items depends on the benefit.13Internal Revenue Service. Modified Adjusted Gross Income For most domestic taxpayers with no foreign income and no tax-exempt interest, MAGI and AGI are the same figure.
The difference shows up if you excluded foreign earned income, received tax-exempt interest, or collected nontaxable Social Security. The Premium Tax Credit adds tax-exempt interest and nontaxable Social Security back to AGI. Roth IRA eligibility adds back items such as the IRA deduction, student loan interest deduction, and excluded foreign earned income. When a form references MAGI, read that form’s instructions; the add-backs are not uniform.
Finding Last Year’s Line 11 for E-File
The most common reason people look up Line 11 has nothing to do with this year’s return. The IRS uses your prior-year AGI as an electronic signature when you e-file, and a mismatch will get your return rejected.14Internal Revenue Service. E-file: Do Your Taxes for Free
Where to find it:
- IRS Online Account at irs.gov, under Tax Records. This is the fastest option.
- A Tax Return Transcript, requested online or by calling 800-908-9946. Look for the “Adjusted Gross Income” line.15Internal Revenue Service. Avoid the Rush: Get a Tax Transcript Online
- Your own copy of last year’s Form 1040, Line 11.
- If you have never filed a federal return before, enter $0.
Mailed transcripts usually arrive in five to ten days, so don’t leave the request until the last week of filing season.
What Goes Wrong If Line 11 Is Off
An error on Line 11 flows into taxable income, changes which credits you qualify for, and moves the final tax number in either direction. The IRS applies an accuracy-related penalty of 20 percent of any underpayment caused by a substantial understatement, which for individuals means the reported tax was off by the greater of 10 percent of the correct amount or $5,000.16Internal Revenue Service. Accuracy-Related Penalty
Before filing, cross-check every income figure on Line 9 against your W-2s, 1099s, and other reporting documents, and confirm each Schedule 1 adjustment is backed by its supporting form (Form 8889 for HSA contributions, Form 1098-E for student loan interest, and so on). If you catch a mistake after filing, submitting Form 1040-X before the IRS contacts you reduces the penalty risk.