This guide is aimed at Australian residents who are US citizens, green card holders, or otherwise required to file a US federal return. An Australian tax return won't show MAGI either, so the US form is where the work happens.
Key Takeaways
- No single MAGI line exists on Form 1040, Form W-2, or Form 1099.
- AGI is the starting point, but the add-backs depend on the benefit being tested.
- Taxable income is not a substitute, because deductions come off after AGI.
- Check Australian income, Form 2555 exclusions and foreign tax credits against current IRS instructions.
Is MAGI Printed on Form 1040?
No. The 2025 Form 1040 shows total income on line 9, AGI on line 11a, deductions on lines 12 to 14, and taxable income on line 15. Nothing is labelled MAGI. Line numbers shift between tax years, so confirm them against the year you're working on.
What the front page tells you
- Line 9: total income
- Line 11a: AGI, your baseline for every MAGI calculation
- Line 15: taxable income, which is not MAGI
Where W-2s, 1099s and software fit
Form W-2 reports wages and withholding. Forms 1099-INT and 1099-DIV report interest and dividends. They are information returns for individual income items, not MAGI statements.
Tax software may calculate MAGI inside a worksheet or eligibility screen, but that figure usually doesn't appear on the filed return.
The Australian angle
An Australian tax return doesn't use Form 1040. First work out whether you have a US filing obligation. US citizens and resident aliens are generally taxed on worldwide income, even while living in Australia, as Publication 54 explains.
Which form you use depends on status:
- Form 1040: green card holders and people who meet the substantial presence test (treated as US residents)
- Form 1040-NR: nonresident aliens
How to Calculate MAGI from Form 1040
Identify the MAGI calculation you need
Decide the purpose before you calculate anything. Each of these uses its own add-back list:
- Roth IRA eligibility
- Traditional IRA deduction
- Premium Tax Credit
- Medicare IRMAA
- Student loan interest deduction
One taxpayer can end up with several different MAGI figures in the same year. The IRS describes this on its MAGI page.
Start with AGI
Review the income on your return, subtract the above-the-line adjustments, and take the resulting AGI from line 11a. Don't substitute gross income, taxable income, or the wages on your W-2.
Add only the modifications required
For tax year 2025, the add-backs vary by provision:
| Purpose | Common add-backs |
|---|---|
| Roth IRA | Traditional IRA deduction, student loan interest deduction, Form 2555 exclusions and housing deduction, excluded savings bond interest, excluded adoption benefits |
| Traditional IRA deduction | Student loan interest, Form 2555 amounts, savings bond interest, adoption benefits |
| Student loan interest | Form 2555 exclusions and housing deduction, certain territory income exclusions |
| Premium Tax Credit | Tax-exempt interest, Form 2555 amounts, nontaxable Social Security |
| Medicare IRMAA | Tax-exempt interest |
None of these lists applies universally. Always follow the worksheet for the specific rule.
Australian income and foreign items
Check whether you excluded foreign earned income on Form 2555, claimed foreign taxes as a credit on Form 1116, or reported foreign housing amounts. A foreign tax credit is a credit against US tax, not an adjustment to AGI.
Excluded earned income is added back in several, but not all, MAGI calculations. For foreign currency amounts, the IRS generally expects you to use the rate prevailing when the item was received, paid or accrued, and to apply that rate consistently.
Check what stays out
Income that is not in AGI and not listed as an add-back for your chosen test generally stays outside that calculation. But tax-exempt or nontaxable status alone doesn't guarantee exclusion. Tax-exempt interest, for instance, is added back for IRMAA and the Premium Tax Credit.
Apply the formula
MAGI = AGI + required modifications.
For example, you want to know if you can contribute to a Roth IRA. Open the Roth worksheet in the current Publication 590-A.
Enter line 11a, adjust for any conversions, and add back only the items that worksheet lists. Then compare the result with the phase-out range for your filing status and year. Don't rely on thresholds from older articles.
AGI vs. MAGI vs. Taxable Income
- AGI: income after specified adjustments, before the standard or itemized deduction
- MAGI: AGI modified for a specific tax rule
- Taxable income: the amount used to calculate federal income tax, after deductions
The standard deduction for 2025 is $15,750 for single filers and $31,500 for married filing jointly. It reduces taxable income, not AGI, so it doesn't lower the figure most income tests use.
Use line 15 by mistake and you could understate your income by tens of thousands of dollars, then contribute to a Roth IRA you aren't eligible for. MAGI is often equal to or higher than AGI when add-backs apply, and it isn't one permanent number.
Why MAGI Matters
Common tax and benefit uses
MAGI gates eligibility, limits, deductions, subsidies and surcharges. It doesn't measure tax owed. Programs and deductions that use MAGI include:
- Roth IRA contributions
- Traditional IRA deductions
- Student loan interest deduction
- Premium Tax Credit
- Medicaid and CHIP income tests (state limits vary)
- Medicare IRMAA
- Net Investment Income Tax
Thresholds, phase-outs and look-backs
A threshold can give full benefit below a limit, partial benefit across a phase-out range, and nothing above it.
For 2025, the Roth IRA phase-out is $150,000 to $165,000 for single filers and $236,000 to $246,000 for joint filers, per Publication 590-A. The Net Investment Income Tax of 3.8% applies above $200,000 for single filers and $250,000 for joint filers.
Some programs look back. Medicare IRMAA for 2026 premiums generally uses income from 2024, so a one-off gain two years ago can raise premiums today. Verify current look-back rules before you rely on a figure.
Cross-border issues for Australian readers
Several items can change the numbers feeding a US MAGI calculation:
- Foreign wages and Australian investment income
- Foreign retirement arrangements, including superannuation
- Currency conversion
- Foreign tax credits and income exclusions
Treatment of superannuation depends on the facts. The US-Australia treaty has a saving clause that lets the US tax its citizens, so there's no blanket exemption.
Reconcile your US schedules and supporting records before making IRA contributions or claiming an income-tested benefit. One catch: excluded foreign earned income generally doesn't count as IRA compensation, even when it's added back for MAGI.
When professional support helps
If your records span two tax systems, a second pair of eyes saves time. VJM Global works with Australian businesses and clients on cross-border tax and advisory matters. Its US-focused services include Form 1040 and 1040-NR preparation. Scope and fees depend on your circumstances, so confirm them directly.
Final Checklist: Find and Calculate MAGI Correctly
Documents to gather
- The applicable Form 1040 or 1040-NR, with schedules
- Forms W-2 and 1099
- Australian income records and payment summaries
- Form 2555 or Form 1116, with supporting records
- Retirement contribution details
- The IRS worksheet for your specific MAGI test
Also check Form 8938 and FBAR obligations. They are separate from MAGI. FBAR applies when foreign account balances exceed US$10,000 in aggregate at any time during the year.
Mistakes to avoid
- Hunting for a MAGI line that doesn't exist
- Using line 15 taxable income instead of AGI
- Applying the same add-backs to every test
- Ignoring foreign income
- Using the wrong tax year or filing status
Locate AGI, confirm the exact purpose of the calculation, and apply only the modifications that test requires. Get qualified advice when Australian and US rules overlap.
Frequently Asked Questions
Where do I find MAGI on my Form 1040?
You won't find it. Form 1040 doesn't print MAGI. Take AGI from line 11a (line numbers can change by year), then use the worksheet for your specific tax rule.
What is the difference between MAGI and AGI?
AGI is the adjusted income figure on Form 1040. MAGI starts with AGI and adds back items required for a particular benefit, deduction or surcharge.
What income is not counted in MAGI?
There's no universal exclusion list. Income outside AGI and not required as an add-back for your chosen test may stay out, but check the result against the relevant IRS rules.
