What is Adjusted Gross Income (AGI)?
Definition
Adjusted Gross Income (AGI) is your total gross income minus specific deductions established by the IRS. It serves as the baseline number used to calculate your taxable income and determines your eligibility for numerous tax deductions and credits. In short, AGI is the most consequential number on your federal tax return.
The IRS definition of AGI explicitly states that it includes all wages, dividends, capital gains, business income, and retirement distributions, before applying standard or itemized deductions.
How to Calculate Your AGI
Calculating your AGI requires a two-step process: determining your gross income and subtracting your "above-the-line" deductions (also known as adjustments to income).
Gross Income - Adjustments to Income = Adjusted Gross Income (AGI)
1. Gross Income
Your gross income encompasses all income you receive throughout the year that is not explicitly exempt from taxation. This includes your salary, hourly wages, tips, self-employment income, rental income, unemployment compensation, and any capital gains realized from selling investments.
2. Adjustments to Income
Once you have your gross income, you subtract specific adjustments. These deductions reduce your AGI and are available regardless of whether you choose to take the standard deduction or itemize your deductions later in the tax return process. Common adjustments include:
- Contributions to a Traditional IRA
- Contributions to a Health Savings Account (HSA)
- Student loan interest payments (up to $2,500)
- Educator expenses (for K-12 teachers)
- Alimony payments (for divorce agreements finalized before 2019)
- Self-employed health insurance premiums
Why Your AGI Matters
Your AGI is the gatekeeper for your tax liability. It directly influences how much you will owe to the federal government in several ways.
First, it is the starting point for calculating your taxable income. After establishing your AGI, you subtract either the standard deduction or your total itemized deductions to arrive at your final taxable income. This taxable income is what dictates your marginal tax bracket.
Second, many tax credits and deductions phase out or disappear entirely once your AGI crosses certain thresholds. For example, your ability to directly contribute to a Roth IRA, claim the Child Tax Credit, or deduct student loan interest is strictly determined by your AGI (or your Modified Adjusted Gross Income, which adds back a few specific deductions). If your AGI is too high, you lose these benefits.
