Below-the-Line Deduction

Full explanation

Below-the-line deductions are subtracted from your AGI to arrive at taxable income. The two options: take the standard deduction ($16,100 single, $32,200 married filing jointly, $24,150 head of household for 2026) or itemize deductions on Schedule A. Unlike above-the-line deductions, below-the-line deductions don't reduce your AGI — so they don't affect AGI-based phase-outs for credits. Common itemized (below-the-line) deductions: state and local taxes (SALT, capped at $10,000), mortgage interest, charitable contributions, and medical expenses exceeding 7.5% of AGI. About 89% of taxpayers take the standard deduction.

Source: IRS Publication 17 — Standard and Itemized Deductions