Qualified Business Income Deduction

The qualified business income deduction is the deduction at Internal Revenue Code section 199A of up to 20 percent of qualified business income from a domestic trade or business operated as a sole proprietorship, partnership, S corporation, trust or estate, plus 20 percent of qualified real estate investment trust dividends and publicly traded partnership income. It is commonly called the QBI deduction or the pass-through deduction, and both names describe the same provision. The deduction is taken by the owner on their individual return, not by the business, which is why an S corporation files a return showing income and never shows this deduction anywhere on it.

Three income bands, and the middle one is where the complexity lives. Below the threshold amount in section 199A(e)(2), which is $201,750 of taxable income for 2026, $403,500 on a joint return and $201,775 filing separately, the calculation is close to simple. The deduction is 20 percent of qualified business income, capped by 20 percent of taxable income excluding net capital gain. No wage test applies, no property test applies, and it does not matter what line of work the business is in.

Above the top of the phase-in range, which is $276,750 for 2026 and $553,500 on a joint return, both restrictions apply in full. The deduction for each trade or business becomes limited to the greater of 50 percent of the W-2 wages that business paid, or 25 percent of those wages plus 2.5 percent of the unadjusted basis immediately after acquisition of its qualified property. And if the business is a specified service trade or business, its income is not qualified business income at all, so the deduction on it is zero.

Between those two points the restrictions phase in proportionally, and for a specified service trade or business the phase-in bites twice, because only the applicable percentage of that business's income, wages and property is counted under section 199A(d)(3)(A)(ii) while the wage limit is simultaneously tightening. The result falls faster than a straight line. Descriptions that present the deduction as a simple on-or-off test at the threshold are describing a two-band system that does not exist.

The 2025 law made three changes, and two of them are easy to miss. The first is permanence, achieved by deletion rather than by a permanence clause. Section 199A(i) previously read, in full, "This section shall not apply to taxable years beginning after December 31, 2025." Public Law 119-21 replaced that subsection generally, so the sunset is simply gone and (i) now does something else. The second is that the width of the phase-in range doubled. Section 199A(b)(3)(B) and section 199A(d)(3) now read "the threshold amount plus $75,000 ($150,000 in the case of a joint return)," where they previously said $50,000 and $100,000. That width is statutory and not indexed, and it is a genuine tax cut for owners inside the range while changing nothing at either end. The third is the new minimum deduction described below. All three apply to taxable years beginning after December 31, 2025, so 2026 is the first year they operate. Guidance written before mid-2025 describes a provision that was scheduled to expire, with a phase-in range half as wide.

The new minimum deduction is a floor on the deduction gated by a threshold on income, and those are two different quantities. Section 199A(i) now provides that for an applicable taxpayer the deduction "shall be equal to the greater of" the amount otherwise computed "or $400." An applicable taxpayer is one whose aggregate qualified business income from all active qualified trades or businesses is at least $1,000. Two points follow that are easy to state wrongly. The income gate is a cliff, so a taxpayer just below it gets nothing from the floor. And "active" carries weight, because the statute defines an active qualified trade or business as one "in which the taxpayer materially participates (within the meaning of section 469(h))," so a passive rental that produces qualified business income does not count toward the gate. The floor also does not rescue a high-income service business. Above the phase-in range a specified service trade or business is not a qualified trade or business, so its income is not qualified business income, so its owner has no aggregate qualified business income and is not an applicable taxpayer at all.

The specified service category is narrower than the statute alone suggests, and this is the single most consequential point on the page. Section 199A(d)(2) borrows a list from section 1202(e)(3)(A) covering services in health, law, accounting, actuarial science, performing arts, consulting, athletics, financial services and brokerage services, and adds investing and investment management, trading, and dealing in securities. Read on its own, the borrowed list closes with "any trade or business where the principal asset of such trade or business is the reputation or skill of 1 or more of its employees," which sounds as though any business built on the owner's expertise is caught. Treasury Regulation section 1.199A-5(b)(2)(xiv) says otherwise, and says it "for purposes of section 199A(d)(2) ... only." That catch-all means exactly three things: income for endorsing products or services, income for the use of an individual's image, likeness, name, signature, voice or trademark, and fees for appearing at an event or in a media format. A contractor, a designer, a machinist or a marketing agency is not swept in by the reputation clause.

Two further adjustments to the borrowed list matter. Section 199A(d)(2)(A) applies section 1202(e)(3)(A) "without regard to the words 'engineering, architecture,'" so engineering and architecture firms are not specified service businesses even though they appear in the borrowed text. And it substitutes "employees or owners" for "employees," widening the reputation clause to reach an owner. Section 199A pulls in only subparagraph (A) of section 1202(e)(3), so banking, insurance, financing, leasing and farming, which are excluded businesses for the separate qualified small business stock rules, are not specified service businesses here. There is also a de minimis rule at Treasury Regulation section 1.199A-5(c)(1)(i): for a business with gross receipts of $25 million or less, it "is not an SSTB if less than 10 percent of the gross receipts" come from a listed field.

The computation runs per trade or business and then combines. For each business, take 20 percent of its qualified business income, which means the net income of a domestic trade or business, reduced by the deductible part of self-employment tax, self-employed health insurance and self-employed retirement contributions attributable to it, and by any amount deducted as qualified tips under section 224. Investment income, capital gain, reasonable compensation paid to an S corporation shareholder and guaranteed payments to a partner are all excluded from qualified business income by section 199A(c) and (d). Apply the wage and property limit if taxable income is above the threshold. Then combine the results across businesses, add 20 percent of qualified real estate investment trust dividends and publicly traded partnership income, and cap the total at 20 percent of taxable income excluding net capital gain.

A hypothetical example, using round numbers rather than statutory ones. Priya runs a bookkeeping business as a sole proprietor. Her qualified business income for the year is $80,000, her taxable income after the standard deduction is $95,000, and she has no capital gain. Because her taxable income is well below the threshold, no wage or property limit applies. Twenty percent of her qualified business income is $16,000. Twenty percent of her taxable income is $19,000. The deduction is the lesser of the two, so she deducts $16,000. Her adjusted gross income does not change, and neither does her self-employment tax.

Two structural points the arithmetic hides. The first is where the deduction sits. It is a below-the-line deduction, available whether or not the filer itemizes, and section 62(a) expressly prevents it from reducing adjusted gross income however large it is. That matters because a long list of other tax rules is measured against adjusted gross income, and this deduction moves none of them. It also does not reduce self-employment tax, which runs on net earnings from self-employment under a separate chapter of the code.

The second is a filing deadline buried inside the wage limit. Section 199A(b)(4)(C) excludes from W-2 wages any amount "not properly included in a return filed with the Social Security Administration on or before the 60th day after the due date" for that return. So a business that files its wage reports late can shrink its own owner's deduction, which is an unusually indirect consequence of a payroll administration failure.

The second limb of the deduction is often omitted entirely. Section 199A(a)(1)(B) allows 20 percent of qualified real estate investment trust dividends and qualified publicly traded partnership income with no wage or property limit and no service-business test. Any investor holding a real estate investment trust in a taxable brokerage account may have this piece of the deduction without owning a business at all, and it arrives on a Form 1099-DIV rather than a business return.

Pros

• Reduces the effective tax rate on business profit by up to a fifth for an owner whose income sits below the threshold.
• Available without itemizing, so it stacks with the standard deduction.
• Now permanent, which removes the planning distortion of an expiring provision.
• The phase-in range is wider from 2026, so owners of service businesses keep a partial deduction $25,000 further up the income scale, or $50,000 on a joint return.
• The real estate investment trust and publicly traded partnership piece is available to investors with no business at all and no restrictions attached.

Cons

• The specified service exclusion falls on doctors, lawyers, accountants, consultants and financial professionals precisely as their income rises, which is when a deduction is worth most.
• The middle band requires a real computation, and the interaction of a phasing-in wage limit with a phasing-out service business is one of the fiddliest calculations in the individual code.
• It reduces taxable income only. Self-employment tax, adjusted gross income and every threshold measured against adjusted gross income are untouched.
• It is computed per trade or business, so an owner with several activities has several computations and has to decide whether aggregation is available.
• The wage limit can reward hiring and owning property for tax reasons rather than business reasons, which is a poor basis for either decision.