What Does Above the Line and Below the Line Mean in Taxes?

Above-the-line and below-the-line deductions are the two categories of subtractions on a federal tax return, split by where they fall relative to your Adjusted Gross Income. Above-the-line deductions come off your income before AGI is calculated and are available whether you itemize or not. Below-the-line deductions come off after AGI, and you have to choose between taking the standard deduction or itemizing to claim them. The split matters because AGI controls eligibility for a long list of credits and tax benefits, so a deduction that lowers AGI often does more work than one that doesn’t.

What the Line Is

The line is your Adjusted Gross Income, the figure that appears partway down Form 1040. AGI starts with every dollar you earned during the year — wages, investment income, business profits, retirement distributions — and then subtracts a specific list of adjustments spelled out in the tax code.¹ What remains is AGI.

AGI is a gateway number. It determines whether you qualify for credits, deductions, and exemptions that carry income limits. Two people earning identical salaries can end up with very different AGIs if one claims more above-the-line deductions, and that gap ripples through the rest of their returns.

Above-the-Line Deductions

Above-the-line deductions are reported on Schedule 1 of Form 1040 and subtracted from gross income before AGI is calculated. You can claim them whether you take the standard deduction or itemize.

Deductions Available to Employees

K–12 teachers, counselors, principals, and aides who work at least 900 hours in a school year can deduct up to $300 in unreimbursed classroom supplies. Married couples who are both eligible educators can each claim $300, for a combined $600 on a joint return.²

If you’re repaying student loans, you can deduct up to $2,500 in interest paid during the year without itemizing. Your lender sends Form 1098-E if you paid $600 or more in interest.³ For 2026, the full deduction is available to single filers with modified AGI of $85,000 or less and joint filers at $175,000 or less. It phases out completely at $100,000 (single) and $205,000 (joint).

Retirement and Health Savings Accounts

Traditional IRA contributions are deductible above the line if you meet the income rules. For 2026, the maximum contribution is $7,500, or $8,600 if you’re 50 or older.⁴ If you or your spouse is covered by a workplace retirement plan, the deduction phases out at set income levels. Single filers covered by a workplace plan lose the full deduction between $81,000 and $91,000 of modified AGI in 2026; joint filers face a phase-out range of $129,000 to $149,000.⁵

Health Savings Account contributions come off above the line as well. For 2026, the annual limit is $4,400 for self-only coverage and $8,750 for family coverage.⁶ You need a qualifying high-deductible health plan to be eligible.

Deductions for the Self-Employed

Self-employed workers get a few above-the-line deductions wage earners don’t. You can deduct half of the self-employment tax you owe, which offsets part of the fact that you’re paying both the employer and employee shares of Social Security and Medicare.⁷ You can also deduct 100% of health insurance premiums paid for yourself and your family, as long as you aren’t eligible for coverage through an employer (including a spouse’s employer) and the deduction doesn’t exceed your net self-employment income.

Active-duty military members can deduct moving expenses above the line. They’re one of the few groups still eligible for that deduction after the 2017 tax law changes.¹

Below-the-Line Deductions: Standard or Itemized

After AGI is set, you subtract either the standard deduction or your itemized deductions, whichever is larger. These are “below the line” because they reduce taxable income after AGI is already locked in, so they don’t affect any income-based eligibility test tied to AGI.

The Standard Deduction

The standard deduction is a flat amount based on filing status. For 2026:⁸

Single or married filing separately: $16,100
Married filing jointly or surviving spouse: $32,200
Head of household: $24,150

Taxpayers who are 65 or older or blind receive an additional standard deduction amount on top of these figures. Because the standard deduction requires no receipts, most filers choose it.⁹

Itemized Deductions

If your deductible expenses exceed the standard deduction, you can list them individually on Schedule A. The major categories are state and local taxes, mortgage interest, charitable contributions, and medical and dental expenses.

State and local taxes cover property taxes plus either state income taxes or sales taxes. For 2026, the cap on this deduction is $40,000, up from the $10,000 limit that applied from 2018 through 2024. High earners may face a reduced cap. Mortgage interest is deductible on up to $750,000 of acquisition debt for a primary or second home ($375,000 if married filing separately). Cash gifts to public charities are deductible up to 60% of AGI, with lower limits for non-cash gifts and certain organizations.¹⁰ Medical and dental expenses are deductible only to the extent they exceed 7.5% of AGI. If your AGI is $80,000, your first $6,000 in medical costs produces no deduction.¹¹

Itemizing requires recordkeeping throughout the year: receipts, mortgage statements, property tax records, and donation acknowledgment letters. The effort only pays off when your total itemized deductions exceed the standard deduction for your filing status.

Why the Distinction Matters

The practical reason to care about above the line versus below the line is that above-the-line deductions lower AGI, and a lower AGI can make you eligible for tax credits worth far more than an equivalent deduction. Credits reduce your actual tax bill dollar-for-dollar. Deductions only reduce the income the bill is calculated on.

The Child Tax Credit is a clear example. For returns filed in the 2026 filing season, the credit begins phasing out at $200,000 of AGI for head-of-household filers and $400,000 for married couples filing jointly. Every $1,000 of AGI above those thresholds reduces the credit by $50. A taxpayer near the cutoff who claims an above-the-line IRA deduction might preserve hundreds of dollars in credit that would otherwise disappear.

The medical expense deduction also hinges on AGI: the 7.5% floor means a lower AGI lets you deduct a larger share of medical costs. The student loan interest deduction and the traditional IRA deduction carry their own AGI-based phase-out ranges. Eligibility for the Premium Tax Credit for health insurance bought through the ACA marketplace depends on household income measured against the federal poverty level. For 2026, the expanded eligibility rules in place since 2021 expired, so the credit is once again limited to households with income between 100% and 400% of the poverty line.

Below-the-line deductions don’t touch any of that. They lower taxable income and nothing else. That’s still valuable, but it’s a narrower kind of value.

Where the Qualified Business Income Deduction Fits

The Section 199A deduction for qualified business income sits outside the above-the-line and below-the-line framework. It’s calculated after AGI and after the standard or itemized deduction, but it isn’t part of either. It’s a separate subtraction that reduces taxable income.¹²

If you earn income through a sole proprietorship, S corporation, partnership, or certain rental activities, you may be able to deduct up to 20% of that qualified business income. For 2026, taxpayers with taxable income below roughly $200,000 (single) or $400,000 (joint) can generally claim the full deduction without worrying about wage or property limitations. Above those thresholds, the deduction phases out for service-based businesses and becomes limited by the wages the business pays. Starting in 2026, the law also guarantees a minimum $400 deduction for qualifying taxpayers with at least $1,000 in business income.¹²

1
Office of the Law Revision Counsel. 26 USC 62 – Adjusted Gross Income Defined
2
Internal Revenue Service. Topic No. 458, Educator Expense Deduction
3
Internal Revenue Service. Topic No. 456, Student Loan Interest Deduction
4
Internal Revenue Service. Retirement Topics – IRA Contribution Limits
5
Internal Revenue Service. 401(k) Limit Increases to $24,500 for 2026, IRA Limit Increases to $7,500
6
Internal Revenue Service. Notice 26-05 – 2026 HSA Limits
7
Internal Revenue Service. Topic No. 554, Self-Employment Tax
8
Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026, Including Amendments From the One, Big, Beautiful Bill
9
Internal Revenue Service. Deductions for Individuals: What They Mean and the Difference Between Standard and Itemized Deductions
10
Internal Revenue Service. Charitable Contribution Deductions
11
Internal Revenue Service. Tax Basics: Understanding the Difference Between Standard and Itemized Deductions
12
Office of the Law Revision Counsel. 26 USC 199A – Qualified Business Income