⚠️ Educational only. TaxPlain does not provide tax, legal, or financial advice. Always consult a qualified tax professional about your specific situation.
What this term is
MAGI stands for Modified Adjusted Gross Income — a tweaked version of your AGI (Adjusted Gross Income) that the IRS uses to decide whether you qualify for certain tax benefits. It's not a line on your tax return. It's a number you calculate behind the scenes when checking eligibility for Roth IRAs, ACA health insurance subsidies, student loan interest deductions, and more.
Think of AGI as your baseline income score. MAGI takes that score and adds back specific deductions you already subtracted — which usually makes MAGI equal to or higher than AGI. That higher number is what the IRS uses to phase out benefits as your income rises.
AGI vs. MAGI
✓ AGI (Adjusted Gross Income)
Your total income minus "above-the-line" adjustments like IRA contributions, student loan interest, and half of self-employment tax. AGI appears on Line 11 of Form 1040. It determines your tax bracket and many standard deductions.
↑ MAGI (Modified AGI)
Your AGI plus certain deductions added back in. MAGI is almost always the same as or higher than AGI. Different programs add back different items — so your "MAGI for Roth IRA" and your "MAGI for ACA subsidies" may not be the same number.
💡 The key insight
There is no single MAGI formula. The IRS defines MAGI differently depending on what you're applying for. Before contributing to a Roth IRA or claiming a subsidy, always calculate MAGI using the rules for that specific program — not a generic online calculator.
What MAGI is used for
Programs that depend on your MAGI
MAGI is the gatekeeper for income-limited tax benefits. Here are the most common ones:
Roth IRA contributions — Direct Roth contributions are limited or blocked above certain MAGI thresholds. Excess contributions trigger a 6% penalty every year until removed.
Traditional IRA deductibility — If you or your spouse has a workplace retirement plan, MAGI determines whether your traditional IRA contribution is fully deductible, partially deductible, or not deductible at all.
ACA premium tax credits — Marketplace health insurance subsidies are based on household MAGI. Earn too much and subsidies shrink or disappear — sometimes creating a surprise tax bill at filing time.
Student loan interest deduction — You can deduct up to $2,500 in student loan interest, but the deduction phases out above MAGI limits ($75,000–$90,000 single / $155,000–$185,000 married filing jointly for 2024).
Child Tax Credit phase-out — While the base credit uses AGI, some related calculations and state programs reference MAGI-style income measures.
Medicare premiums (IRMAA) — Higher-income retirees pay surcharges on Medicare Part B and Part D premiums based on MAGI from two years prior.
Net Investment Income Tax (NIIT) — The 3.8% surtax on investment income applies when MAGI exceeds $200,000 (single) or $250,000 (married filing jointly).
2024 income limits
Key MAGI thresholds to know
These limits change annually. Here are the 2024 numbers for the most searched programs:
Roth IRA (single) — Full contribution if MAGI under $146,000. Partial contribution $146,000–$161,000. No direct Roth above $161,000 (backdoor Roth may still be an option).
Roth IRA (married filing jointly) — Full contribution if MAGI under $230,000. Partial $230,000–$240,000. No direct Roth above $240,000.
Traditional IRA deductibility (single, covered by workplace plan) — Full deduction if MAGI under $77,000. Partial $77,000–$87,000. No deduction above $87,000.
Traditional IRA deductibility (MFJ, contributor covered) — Full deduction if MAGI under $123,000. Partial $123,000–$143,000. No deduction above $143,000.
ACA subsidies — Based on household MAGI as a percentage of the federal poverty level. For 2024 coverage, subsidies generally apply up to 400% of FPL (~$58,320 for an individual), with enhanced credits extending further under current law.
This is the most common MAGI calculation. Start with your AGI from Line 11 of Form 1040, then add back:
Traditional IRA deduction — If you deducted a traditional IRA contribution, add it back
Student loan interest deduction — Add back whatever you deducted on Schedule 1
Foreign earned income exclusion — Add back excluded foreign wages (Form 2555)
Foreign housing exclusion or deduction — Add back excluded housing amounts
Excluded adoption benefits — Add back employer-provided adoption assistance you excluded from income
Excluded income from U.S. territories — Add back Puerto Rico or American Samoa source income you excluded
For ACA subsidy MAGI, the formula is different: start with AGI, then add tax-exempt interest, non-taxable Social Security benefits, and excluded foreign income. Tax software and the Healthcare.gov calculator handle this, but verify the inputs match your actual return.
Common mistakes to avoid
⚠️ Assuming AGI = MAGI
If you took a student loan interest deduction or traditional IRA deduction, your MAGI is higher than your AGI. Using AGI alone can make you think you're eligible when you're not — leading to excess Roth contributions and a 6% annual penalty.
⚠️ One MAGI for everything
Your Roth IRA MAGI and your ACA MAGI use different add-back rules. Calculating one and applying it to both programs is a common error that causes surprise disqualifications or subsidy repayments at tax time.
⚠️ Ignoring year-end income spikes
A bonus, stock sale, or Roth conversion late in the year can push your MAGI over a threshold you weren't planning for. Estimate MAGI before making large financial moves — especially Roth conversions, which themselves increase MAGI.
⚠️ Forgetting spouse's income
MAGI limits for married filing jointly combine both spouses' income. A stay-at-home spouse can't contribute to a Roth at the single-filer limit if the working spouse's income pushes household MAGI over the joint threshold.
What to do right now
Pull up last year's Form 1040 and find Line 11 (AGI). Before contributing to a Roth IRA, making a traditional IRA contribution you plan to deduct, or estimating ACA subsidies, run the MAGI calculation for that specific program. If you're near a threshold, a tax professional can model how a bonus, capital gain, or Roth conversion would affect your eligibility — sometimes shifting a contribution to January or using a backdoor Roth saves thousands in penalties or lost subsidies.
Questions to ask your tax professional
01What is my MAGI for Roth IRA purposes this year, and am I inside the contribution limit?
02Should I use a backdoor Roth conversion given my MAGI — and how do I avoid the pro-rata rule trap?
03How will a Roth conversion or capital gain affect my MAGI and ACA subsidy eligibility?
04Is my traditional IRA contribution deductible based on my MAGI and workplace plan coverage?
05Am I still eligible for the student loan interest deduction at my current MAGI?
06What income-reduction strategies (HSA, 401k deferrals, timing deductions) can keep my MAGI below key thresholds?
Frequently asked questions
Is MAGI the same as taxable income?
No. Taxable income is what you actually pay tax on — AGI minus either the standard or itemized deduction. MAGI starts from AGI and adds certain items back in. Taxable income is usually lower than both AGI and MAGI because it includes the standard deduction ($14,600 single for 2024).
Where do I find MAGI on my tax return?
You won't — MAGI isn't a line on Form 1040. You calculate it separately based on which program you're checking eligibility for. Your AGI is on Line 11. From there, you add back the specific items that program requires.
Does a 401(k) contribution reduce MAGI?
Traditional 401(k) contributions reduce your AGI (they're pre-tax), which also reduces MAGI since MAGI starts from AGI. Roth 401(k) contributions do not reduce AGI or MAGI — they're made with after-tax dollars. This is why maxing out a traditional 401(k) can help keep MAGI below Roth IRA or ACA thresholds.
What happens if I over-contribute to a Roth IRA because of MAGI?
The IRS charges a 6% excise tax on excess contributions for every year they remain in the account. Fix it by withdrawing the excess plus earnings before your tax filing deadline (including extensions). You can also recharacterize the contribution as traditional, though recharacterization rules have tightened since 2018.
Can MAGI be lower than AGI?
Generally no — MAGI equals AGI plus add-backs, so it's the same or higher. The one exception: for certain Medicaid and CHIP eligibility calculations, MAGI may exclude specific income types that AGI includes, making it lower in those narrow contexts. For tax purposes (Roth IRA, ACA, student loans), MAGI is always ≥ AGI.