MAGI vs. AGI: What’s the Difference?

Adjusted gross income (AGI) and modified adjusted gross income (MAGI) are two ways to calculate what your income might be for tax purposes. Both these figures directly influence your tax obligations, qualifying for certain tax benefits and deductions. Therefore, knowing when each applies can support your tax-saving strategies and inform financial decisions.

A financial advisor can help you better understand how different types of income impact your taxes and retirement strategy.

Understanding Adjusted Gross Income (AGI)

AGI, or adjusted gross income, is your total income. This includes wages, interest, dividends and capital gains, minus specific deductions or adjustments. The IRS uses your AGI to calculate the portion of income that Uncle Sam can tax.

However, the IRS excludes certain types of income from your AGI. These may include tax-exempt interest, certain Social Security benefits, and qualified distributions from Roth IRAs.

As an example, let’s say Bob has a total income of $50,000. From this, he has $4,000 in student loan interest and $1,000 in healthcare expenses that are deductible. After these deductions, Bob’s AGI will be $45,000.

How to Calculate AGI

Understanding how to calculate AGI can help you make informed financial decisions and potentially reduce your tax liability. AGI is essentially your total gross income minus specific deductions, known as adjustments. These adjustments can include contributions to retirement accounts, student loan interest and certain business expenses, among others.

The first step in calculating your AGI is to determine your total income for the year. This includes all sources of income, such as wages, dividends, capital gains, business income and any other earnings. It’s important to gather all relevant financial documents, such as W-2s, 1099s and other income statements. This ensures you have a comprehensive view of your earnings. By accurately identifying your total income, you lay the groundwork for calculating your AGI.

Once you have your total income, the next step is to apply the allowable adjustments. These adjustments can significantly impact your AGI and your tax obligations. Common adjustments include contributions to a traditional IRA, health savings account (HSA) contributions and educator expenses if you are a qualified teacher. Additionally, self-employed individuals can deduct half of their self-employment tax. Each of these adjustments reduces your total income, resulting in a lower AGI.

How Does AGI Influence Your Taxes?

Your adjusted gross income (AGI) plays a significant role in determining your federal income tax liability and eligibility for various tax benefits. Here are eight ways in which AGI affects your taxes:

Tax Brackets and Credits

Your AGI helps determine which federal income tax bracket you fall into. Different tax brackets have different tax rates. The IRS uses your AGI to calculate the amount of income subject to each rate. A higher AGI may result in a higher tax rate, leading to a higher income tax liability. Many tax credits have income phaseouts based on your AGI. These include the Child Tax Credit, Earned Income Tax Credit, and the Saver’s Credit. If your AGI exceeds certain thresholds, you may become ineligible for or receive reduced tax credits.

Deductions and Retirement Accounts

Certain itemized deductions, like medical expenses and miscellaneous itemized deductions, have AGI limits. Your ability to claim these deductions may be reduced or limited as your AGI increases. AGI determines your eligibility for above-the-line deductions, too. Also known as adjustments to income, these deductions can reduce your taxable income. They are often available even if you don’t itemize deductions. Examples of above-the-line deductions include contributions to traditional IRAs, student loan interest and alimony paid.

Your AGI influences your ability to contribute to retirement accounts, such as traditional IRAs, Roth IRAs, and employer-sponsored retirement plans like 401(k)s. High AGI can limit or phase out your contributions, while lower AGI may allow you to maximize your contributions.

AMT, NIIT, and Social Security Taxes

The IRS calculates your alternative minimum tax (AMT) based on a modified version of your AGI. If your AGI is relatively high, you may be more likely to trigger the AMT, resulting in a higher overall tax liability. The net investment income tax (NIIT) applies to certain types of investment income and will kick in once your AGI exceeds specific thresholds. It can result in an additional 3.8% tax on net investment income. ¹

The IRS also uses your AGI, in part, to determine how much to tax your Social Security benefits. If your AGI exceeds certain thresholds, some of your Social Security benefits may become taxable. Speaking to a tax professional can help you determine if there are ways to cut down your tax liability.

How Modified Adjusted Gross Income (MAGI) Works

MAGI, or Modified Adjusted Gross Income, is your AGI, with a twist. It includes most of the items that you originally subtracted from your total income to get your AGI but it puts the other deductions back on the table. MAGI includes sources of income not initially covered in your AGI. This includes foreign income, tax-exempt interest, and the excluded portion of Social Security benefits.

How to Calculate MAGI

To calculate MAGI, you start with your Adjusted Gross Income (AGI), which is your total gross income minus specific deductions. You can find your AGI on your tax return as it serves as the foundation for calculating MAGI. Understanding the difference between AGI and MAGI is essential, as MAGI includes additional income sources and deductions that AGI does not.

To arrive at your MAGI, you need to make specific adjustments to your AGI. These adjustments typically involve adding back certain deductions you subtracted to calculate AGI. Common additions include foreign-earned income, student loan interest, and tuition deductions.

Additionally, you should add back any excluded foreign housing costs and tax-exempt interest income. These adjustments ensure that your MAGI reflects a more comprehensive picture of your financial situation, which is crucial for determining eligibility for tax-related benefits.

How Does MAGI Influence Your Taxes?

Your MAGI determines your eligibility for certain tax benefits and assistance programs. Here are eight examples:

• Tax Deductions and credits: MAGI is used to determine eligibility for tax deductions and credits like the student loan interest deduction and the tuition and fees deduction. Additionally, it’s used to calculate income phaseouts for the premium tax credit for health insurance purchased through the health insurance marketplace.
• Roth IRA contributions: MAGI determines eligibility for making contributions to a Roth IRA. If your MAGI exceeds certain limits, you may not be eligible to contribute to a Roth IRA.
• Medicare premiums: For Medicare Part B (medical insurance) and Medicare Part D (prescription drug coverage), your MAGI is used to determine the premiums you pay. Higher MAGI can result in higher Medicare premiums.
• Eligibility for subsidized health insurance: When applying for health insurance through the health insurance marketplace, your MAGI is used to determine your eligibility for premium tax credits and subsidies. Higher MAGI may reduce or eliminate your eligibility for subsidies.
• Financial assistance programs: In some cases, MAGI is used to determine eligibility for various government assistance programs, such as Medicaid and the Children’s Health Insurance Program (CHIP).
• Retirement account deductions: MAGI can affect your ability to deduct contributions to certain retirement accounts, such as traditional IRAs. High MAGI may limit or eliminate your ability to claim these deductions.
• Eligibility for education tax benefits: Your MAGI is used to assess your eligibility for education-related tax benefits, such as the American Opportunity Tax Credit and the Lifetime Learning Credit.

If you don’t fully understand how this impacts you then consider talking to a financial advisor or other tax professional.

AGI vs. MAGI: Key Differences

Modified adjusted gross income (MAGI) and adjusted gross income (AGI) are both important figures in the U.S. tax system, but they have distinct purposes and calculations. Here are seven key differences:

1. Purpose

• The IRS uses AGI for calculating your federal income taxes. It serves as the starting point for determining your taxable income and impacts your federal income tax liability.
• MAGI serves a purpose beyond federal income tax. Different agencies use it to determine eligibility for specific tax benefits, subsidies, and government assistance programs.

2. Calculation Components

• AGI is calculated by subtracting “above-the-line” deductions (such as contributions to Traditional IRAs and student loan interest) from your total income, including wages, business income, interest, and more.
• MAGI is calculated by adding back certain deductions to your AGI, such as the foreign earned income exclusion, tax-exempt interest, and certain deductions related to rental losses.

3. Use in Taxation

• The IRS uses AGI to determine your federal income tax liability. It affects your tax brackets, eligibility for itemized deductions, and various other tax-related calculations.
• It uses MAGI to assess eligibility for specific tax credits, deductions, and subsidies, such as the Premium Tax Credit for health insurance, Roth IRA contributions, and education tax credits.

4. Impact on Tax Credits and Deductions

• AGI directly influences the phase-out of certain deductions, like medical expense deductions, and can affect the amount of itemized deductions you can claim.
• The IRS uses MAGI to assess eligibility for a wide range of tax credits and deductions, including the Child Tax Credit, the Earned Income Tax Credit, and premium tax credits for health insurance.

5. Medicare Premiums

• Medicare does not use AGI directly used to determine the cost of your premiums.
• Medicare Part B and Part D premiums do use MAGI to calculate costs. Higher MAGI can result in higher Medicare premiums.

6. Subsidies and Assistance Programs

• Government assistance programs and subsidies typically do not use AGI to determine eligbility.
• Subsidies related to health insurance, Medicaid, the Children’s Health Insurance Program (CHIP), and other assistance programs use MAGI to determine eligibility.

7. Retirement Contributions

• AGI does not directly impact contributions to retirement accounts like Traditional IRAs.
• MAGI also determines your eligibility for contributions to Roth IRAs. High MAGI may limit or eliminate your ability to contribute to a Roth IRA.

How to Lower Your AGI and MAGI Before Tax Day

Knowing your AGI and MAGI is important because both numbers can affect your taxes, eligibility for deductions and access to certain tax benefits. The good news is that several year-end moves can help lower them.

One of the most common strategies is contributing to a traditional IRA. Eligible contributions reduce your AGI dollar for dollar, potentially lowering your taxable income and helping you qualify for tax breaks that phase out at higher income levels. For 2026, the contribution limit is $7,500, or $8,600 for those age 50 and older, although deduction limits may apply if you or your spouse are covered by a workplace retirement plan. ²

A health savings account (HSA) can provide another valuable deduction. Contributions to an HSA reduce your AGI, grow tax-deferred and can be withdrawn tax-free for qualified medical expenses. For taxpayers who qualify, it is one of the most tax-efficient savings vehicles available.

Self-employed workers may have even more opportunities. Contributions to a SEP IRA or Solo 401(k) can substantially reduce AGI, and the deduction for half of self-employment tax provides an additional adjustment to income.

Investment decisions can also affect AGI and MAGI. Realizing capital losses can offset capital gains and, in some cases, reduce taxable income. Likewise, delaying the sale of appreciated investments until a lower-income year may help keep MAGI below thresholds tied to Medicare surcharges, Roth IRA eligibility and other tax benefits.

For taxpayers near an important income threshold, even a small reduction can make a meaningful difference. Reviewing your AGI and MAGI before the end of the year can give you time to take advantage of strategies that may lower taxes and preserve valuable benefits.

Bottom Line

Understanding the difference between AGI and MAGI can help you make more informed financial decisions throughout the year. Because these two figures affect everything from tax liability to eligibility for credits and deductions, knowing how they’re calculated allows you to plan more effectively. By tracking income, understanding which adjustments apply to you and reviewing how these figures impact your taxes, you can better manage your financial picture and avoid surprises at tax time.

Tips for Tax Planning

• A financial advisor can help you with most financial matters, including tax planning. Their expertise can come in handy with all of your financial activities from making a retirement plan to managing your investments. Finding a financial advisor doesn’t have to be hard. SmartAsset’s free tool matches you with vetted financial advisors who serve your area, and you can have a free introductory call with your advisor matches to decide which one you feel is right for you. If you’re ready to find an advisor who can help you achieve your financial goals, get started now.
• If you want to estimate the potential taxes you might pay, consider using SmartAsset’s free tax calculator.

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