Where Is MAGI on Form 1040? Line 11, Add-Backs, and Formulas

Modified Adjusted Gross Income does not appear on Form 1040. There is no line, box, or worksheet on the return itself labeled MAGI.¹ You calculate it yourself, starting from the Adjusted Gross Income printed on Line 11 of your 1040 and adding back specific income items or deductions depending on which tax provision you are checking. The wrinkle: there is no single MAGI. The add-backs shift depending on whether you are testing Roth IRA eligibility, Premium Tax Credit qualification, Medicare surcharges, the Net Investment Income Tax, or a handful of other benefits.

Start at Line 11

Line 11 of Form 1040 shows your Adjusted Gross Income, and that figure is the starting point for every MAGI calculation.¹ AGI is your total income from wages, interest, dividends, business income, capital gains, and other sources, reduced by the “above-the-line” adjustments listed on Schedule 1.

Those Schedule 1 adjustments include the deductible portion of self-employment tax, Health Savings Account contributions, educator expenses, and student loan interest.² The total flows from Schedule 1, line 26 onto Form 1040, line 10, and is subtracted from total income to produce Line 11. Every MAGI figure you compute begins there.

Why MAGI Is Not on the Form

MAGI takes your Line 11 AGI and adds back certain income items or deductions that were excluded or subtracted along the way. Congress designed it as a way to measure economic capacity before deciding who qualifies for a benefit. If tax-exempt municipal bond interest or excluded foreign earnings could shrink AGI while still funding a household, income-based subsidies would reach people they were never meant to reach. MAGI closes that gap.

Because it only adds items back, MAGI is always equal to or higher than the AGI on Line 11.¹ For many W-2 employees with no municipal bonds, no foreign income, and no unusual exclusions, MAGI and AGI are the same number. The gap opens only when you have the specific income sources or deductions a given provision strips away.

And there is no single MAGI. The IRS maintains different MAGI formulas for Roth IRA contributions, the Child Tax Credit, education credits, the Premium Tax Credit, the Net Investment Income Tax, adoption expenses, and other provisions.¹ Each starts from Line 11 and adds back a different combination of items. Before you compute anything, identify which benefit you are testing, then locate that provision’s worksheet.

The Add-Backs That Push MAGI Above AGI

A short list of items shows up across most MAGI formulas, though not every formula uses every item.

Tax-exempt interest. Interest from municipal bonds escapes federal income tax, but it is added back for Premium Tax Credit, Medicare surcharge, and Social Security benefit calculations. It sits on line 2a of Form 1040.³
Foreign earned income exclusion. Earnings excluded under the rules for U.S. citizens living abroad (Form 2555) are added back for nearly every MAGI test.¹
Non-taxable Social Security benefits. The portion of benefits not included in taxable income is added back for Premium Tax Credit purposes.³
Student loan interest and traditional IRA deductions. Both are Schedule 1 adjustments that already reduced AGI; for Roth IRA MAGI, they are added back.¹
Savings bond interest exclusion. Interest excluded on Form 8815 for higher education expenses is added back for Roth IRA and education credit MAGI.¹

For a taxpayer with large municipal bond holdings or excluded foreign income, the gap between AGI and MAGI can be substantial. For everyone else, it is often nothing.

Which MAGI Formula Goes With Which Benefit

Roth IRA Contributions

The Roth IRA MAGI adds back the traditional IRA deduction, the student loan interest deduction, the savings bond interest exclusion, the employer-provided adoption benefit exclusion, and foreign earned income or housing exclusions. It then subtracts any income from converting a traditional IRA to a Roth or rolling over a qualified plan to a Roth, so conversions do not count against your ability to make new contributions.¹ The worksheet lives in IRS Publication 590-A.⁴

Traditional IRA Deduction

If you or your spouse participates in a workplace retirement plan, the deduction phases out based on MAGI. If neither of you is covered, the phase-out does not apply and the full deduction is available regardless of MAGI.⁵

Premium Tax Credit

The PTC uses the most inclusive MAGI. It equals AGI plus excluded foreign income, non-taxable Social Security benefits (including tier 1 railroad retirement benefits), and tax-exempt interest.³ Household MAGI adds together the MAGI of every family member required to file. The calculation happens on Form 8962.

Medicare IRMAA

Medicare uses the simplest MAGI of any provision: AGI from Line 11 plus tax-exempt interest from line 2a. Nothing else is added. The complication is timing. Social Security sets your 2026 premiums using your 2024 return, or your 2023 return if the 2024 filing was unavailable. A one-time income spike from selling a house, converting a large IRA, or cashing out stock options can raise your premiums two years later. If a qualifying life-changing event (retirement, divorce, death of a spouse) has since reduced your income, you can request a lower determination by filing Form SSA-44.⁶

Net Investment Income Tax

The 3.8% NIIT applies when MAGI exceeds $200,000 for single or head of household, $250,000 for married filing jointly, and $125,000 for married filing separately. The tax hits the lesser of your net investment income or the amount by which MAGI exceeds the threshold. The NIIT MAGI is narrower than the PTC version: AGI plus the foreign earned income exclusion and certain related deductions.⁷ These thresholds are not indexed for inflation and have not changed since the tax took effect in 2013. Form 8960 walks through the calculation.

Rental Real Estate Loss Allowance

If you actively participate in managing a rental, you can generally deduct up to $25,000 in rental losses against other income. That allowance phases out once MAGI exceeds $100,000 and disappears at $150,000; for married couples filing separately who lived apart all year, the allowance is $12,500 with a $50,000 phase-out starting point.⁸⁹ The passive-loss MAGI starts with AGI but ignores taxable Social Security benefits, excludable savings bond interest, the IRA deduction, the student loan interest deduction, and any passive activity loss itself.

Child Tax Credit, Education Credits, and Adoption Credit

The Child Tax Credit MAGI adds back foreign earned income and housing exclusions; for 2026 the credit maxes at $2,200 per qualifying child and phases out at $200,000 for single and head-of-household filers and $400,000 for joint filers.¹ The American Opportunity Tax Credit and the Lifetime Learning Credit use a MAGI that adds back foreign earned income exclusions and foreign housing deductions, with phase-out ranges adjusted annually. The Adoption Tax Credit uses its own MAGI, with a 2025 phase-out running from $259,191 to $299,189.¹⁰

What It Costs to Use the Wrong MAGI

Because MAGI drives eligibility rather than appearing on the return, mistakes surface later, and often with penalties attached.

If your MAGI was too high for a Roth IRA contribution but you contributed anyway, the excess is hit with a 6% penalty tax for every year it remains in the account.¹¹ You can avoid it by withdrawing the excess and any attributable earnings before your filing deadline, including extensions. The same 6% penalty applies to excess traditional IRA and HSA contributions.

For the Premium Tax Credit, the stakes climb in 2026. If your actual MAGI comes in higher than the estimate you gave the Marketplace and you received advance premium payments based on the lower estimate, the full excess is repaid when you file, with no cap on the amount.¹² Prior years capped repayments for households below 400% of the federal poverty line; those caps no longer apply. And starting in 2026 the enhanced subsidies enacted under the American Rescue Plan and Inflation Reduction Act have expired, so eligibility again requires household income between 100% and 400% of the poverty line.¹³

For Medicare IRMAA, the two-year lookback means one high-income year lifts your premiums during a year when your income may already be lower. Form SSA-44 offers relief when a qualifying life-changing event has since cut your income, but the documentation is on you.⁶

The rule that keeps you out of trouble is the same in every case. Identify which MAGI definition applies to the decision in front of you, then use the worksheet built for it. For Roth eligibility, that is Publication 590-A.⁴ For Marketplace enrollment, the Form 8962 instructions. For NIIT, Form 8960. Running the right threshold against the wrong version of MAGI produces the same wrong answer as miscomputing MAGI itself.

1
Internal Revenue Service. Modified Adjusted Gross Income
2
Internal Revenue Service. 2025 Schedule 1 (Form 1040) – Additional Income and Adjustments to Income
3
Internal Revenue Service. Questions and Answers on the Premium Tax Credit
4
Internal Revenue Service. Publication 590-A (2025)
5
Internal Revenue Service. 401(k) Limit Increases to $24,500 for 2026, IRA Limit Increases to $7,500
6
Social Security Administration. Medicare Income-Related Monthly Adjustment Amount – Life-Changing Event Form SSA-44
7
Internal Revenue Service. Questions and Answers on the Net Investment Income Tax
8
Office of the Law Revision Counsel. 26 U.S. Code 469 – Passive Activity Losses and Credits Limited
9
Internal Revenue Service. Instructions for Form 8582
10
Internal Revenue Service. Adoption Credit
11
Internal Revenue Service. Form 5329 – Additional Taxes on Qualified Plans (Including IRAs) and Other Tax-Favored Accounts
12
Internal Revenue Service. Updates to Questions and Answers About the Premium Tax Credit
13
HealthCare.gov. Modified Adjusted Gross Income (MAGI) – Glossary