What Is MAGI? Modified Adjusted Gross Income Explained

MAGI (Modified Adjusted Gross Income) is your AGI with certain deductions “added back.” MAGI determines eligibility for many tax credits, IRA contribution limits, ACA marketplace subsidies, and Medicare premium tiers. Despite the name, MAGI is usually larger than AGI for tax purposes — adding back items that the IRS thinks should count for these specific tests.

The tricky part: MAGI is calculated differently for different purposes. There’s no single “MAGI” — it varies by what you’re trying to determine. Roth IRA MAGI is different from ACA MAGI, which is different from student loan interest MAGI.

The basic MAGI formula

Generic formula (most common version):

MAGI = AGI + tax-exempt foreign income + tax-exempt Social Security + tax-exempt interest

Different programs add back different items. Each variation matters for the specific test it’s used for.

MAGI for Roth IRA eligibility

Roth IRA MAGI = AGI + Traditional IRA deduction + Student loan interest deduction + Foreign earned income exclusion + Excluded employer adoption benefits + Tuition deduction + Domestic production activities deduction

2026 Roth IRA contribution limits:

Filing status	Full contribution	Phased out at	No contribution above
Single	MAGI under $146,000	$146K-$161K	$161,000
Married filing jointly	MAGI under $230,000	$230K-$240K	$240,000
Married filing separately	MAGI under $0	$0-$10K	$10,000

Above these thresholds, you can still contribute via backdoor Roth (contribute to traditional IRA, then convert).

MAGI for ACA (Obamacare) Marketplace Subsidies

ACA MAGI = AGI + tax-exempt foreign income + tax-exempt Social Security + tax-exempt interest

2026 ACA marketplace subsidy thresholds (varies by year and family size):

Family size	400% of FPL (subsidy cap)
1 person	~$60,000 MAGI
2 people	~$81,500 MAGI
4 people	~$125,000 MAGI
Family of 5+	~$143,000+ MAGI

Under American Rescue Plan + Inflation Reduction Act, the 400% cap was temporarily lifted (extended through 2025). For 2026+, depends on legislation.

MAGI for Medicare Part B and D Premiums (IRMAA)

Higher-income retirees pay higher Medicare premiums — IRMAA (Income-Related Monthly Adjustment Amount) based on MAGI from 2 years prior.

Medicare MAGI = AGI + tax-exempt interest

2026 IRMAA brackets (based on 2024 MAGI):

Single	Married joint	Part B addition	Part D addition
Under $103K	Under $206K	$0	$0
$103-$129K	$206-$258K	+$70	+$13
$129-$161K	$258-$322K	+$176	+$33
$161-$193K	$322-$386K	+$282	+$54
$193-$500K	$386-$750K	+$388	+$74
$500K+	$750K+	+$420	+$81

MAGI for Student Loan Interest Deduction

Student Loan MAGI = AGI + Foreign earned income exclusion

2026 thresholds (deduction up to $2,500):

Single: MAGI under $80,000 (full); $80K-$95K (phase-out); above $95K (no deduction)
Married joint: MAGI under $165,000 (full); $165K-$195K (phase-out); above $195K (no deduction)

MAGI for Traditional IRA Deduction (if covered by workplace plan)

If you OR spouse have a 401(k)/workplace retirement plan, traditional IRA deduction phases out based on MAGI:

Traditional IRA MAGI = AGI (similar to Roth MAGI)

2026 thresholds (single, covered by workplace plan):

Full deduction: MAGI under $77,000
Phased: $77K-$87K
No deduction: above $87,000

MAGI for Net Investment Income Tax (NIIT)

The 3.8% NIIT applies to investment income above thresholds:

NIIT MAGI = AGI + Foreign earned income excluded

2026 thresholds:

Single: $200,000
Married joint: $250,000
Married separate: $125,000

MAGI for Education Credits

American Opportunity Tax Credit (AOTC)

Full credit: Single under $80K / Married under $160K
Phase-out: $80-90K / $160-180K
Eliminated above

Lifetime Learning Credit (LLC)

Full credit: Single under $80K / Married under $160K
Phase-out: $80-90K / $160-180K
Eliminated above

How to calculate your MAGI

For most purposes (since MAGI variations are similar):

Find your AGI on Form 1040, Line 11.
Add tax-exempt foreign earned income (Form 2555).
Add tax-exempt Social Security (if any).
Add tax-exempt interest (municipal bond income on Line 2a).

For program-specific MAGI:

Roth IRA: Add back IRA deduction, student loan interest deduction.
ACA: Use AGI + above three items (no add-backs).
Medicare IRMAA: Use AGI + tax-exempt interest only.

Where to find MAGI on tax forms

Form 1040: Line 11 (AGI) is your starting point. Add back items based on your specific purpose.
Form 8606 (IRA): Shows IRA-related MAGI.
Form 8962 (ACA): Shows ACA MAGI.
TurboTax / FreeTaxUSA / H&R Block: All calculate the right MAGI for whichever credit/deduction you’re claiming.

Common MAGI traps

1. Tax-exempt interest counts

Municipal bond interest is generally tax-FREE — but it’s ADDED back for MAGI purposes. This makes municipal bonds less appealing for taxpayers near MAGI thresholds.

2. Foreign earned income exclusion is added back

Living abroad and excluding foreign income from US tax? That excluded income still counts for MAGI tests — which can make you ineligible for ACA subsidies, Roth IRA, etc.

Tax-exempt portion of Social Security counts. People relying on SS benefits should know their full SS amount counts toward IRMAA thresholds.

4. Tax-exempt Roth distributions DON’T add back

Qualified Roth IRA withdrawals don’t appear on AGI at all — they don’t add back for MAGI either. This is a big strategic advantage of Roth in retirement.

5. Retirement plan contributions REDUCE MAGI

Pre-tax 401(k), traditional IRA (if deductible), HSA all REDUCE AGI and therefore MAGI. Useful for staying under MAGI thresholds.

Strategies to reduce your MAGI

Max out HSA contributions ($4,400 single / $8,750 family in 2026, above-the-line)
Max out traditional 401(k) ($23,500 + $7,500 catch-up if 50+ in 2026)
Use Roth conversions in low-income years — converts traditional IRA to Roth (taxable event), then tax-free withdrawals don’t add back
Maximize above-the-line deductions (educator expenses, self-employed health insurance)
Tax-loss harvesting — realize losses to offset gains, reducing AGI
Delay capital gains — push to next year if you’re temporarily over threshold

Frequently asked questions

Q: Is MAGI the same as gross income? A: No. Gross income includes everything you earned. AGI is gross minus certain deductions. MAGI is AGI plus certain add-backs. MAGI is usually larger than AGI but smaller than gross income.

Q: How do I find my MAGI from my tax return? A: Tax software shows it automatically. Manually: start with Form 1040 Line 11 (AGI). Add Form 2555 foreign income, tax-exempt interest, etc. For specific tests, follow IRS Publication 590-A (Roth/IRA), 974 (ACA), or 17.

Q: Why is MAGI different for different tax benefits? A: Each test was created by Congress with its own definition. Some add-backs make sense (foreign income for residency-based credits), others are historical accidents. Always use the right MAGI for the specific benefit you’re claiming.

Q: Can I reduce my MAGI to qualify for ACA subsidies? A: Yes. Pre-tax 401(k), HSA, and deductible IRA contributions all reduce AGI/MAGI. Self-employed health insurance, self-employment tax deduction, and student loan interest also help. Plan these BEFORE year-end for maximum impact.

Tax Calculator — Federal income tax with deductions
Roth IRA Calculator — Contribution growth + MAGI limits
Take-Home Pay — Net pay calculator
Capital Gains Tax — For NIIT analysis

MAGI is one of the most misunderstood tax concepts because there’s no single definition. Always check which MAGI applies to the specific benefit you’re calculating.