The QBI Deduction: How Business Owners Leave 20% on the Table

Most business owners know the QBI deduction exists. Far fewer realize their income, their entity structure, or even their payroll choices may be quietly erasing it. That gap between knowing the rule and actually claiming it is where a surprising amount of tax value disappears every year.

What Section 199A Actually Does, and Who Can Claim It

The Section 199A deduction lets owners of pass-through businesses, sole proprietors, S-corps, partnerships, and certain LLCs, deduct up to 20% of qualified business income from taxable income. On $400,000 of QBI, that is an $80,000 deduction before you negotiate anything. The math matters.

The straightforward version applies to most trades or businesses that are not "specified service trades or businesses" (SSTBs). An SSTB is any business where the principal asset is the skill or reputation of its owners or employees: consulting, law, medicine, financial services, and similar fields. If you run an SSTB, the deduction does not disappear, but it phases out as your income climbs.

For 2026, confirm the exact thresholds with your CPA, but the structure works like this: below a lower taxable income threshold, SSTB owners qualify for the full deduction just like anyone else. Above an upper threshold, the deduction is gone entirely. In between, it phases out ratably. Non-SSTB owners face different limits above the lower threshold, tied to W-2 wages paid and the unadjusted basis of qualified property (UBIA), not a phase-out on the deduction itself.

The W-2 and UBIA limits are the piece most owners miss. Once your income clears the lower threshold, your deduction is capped at either 50% of W-2 wages paid by the business, or 25% of W-2 wages plus 2.5% of UBIA of qualified property, whichever is greater. A profitable S-corp with no employees and minimal fixed assets can find itself holding a deduction that exists in theory and is nearly zero in practice.

The Planning Levers That Actually Move the Number

Three levers do the real work here.

Retirement-plan contributions. The deduction is calculated against taxable income, not gross revenue. A SEP-IRA, Solo 401(k), or defined benefit plan contribution reduces your W-2 income and your QBI simultaneously, which can pull your taxable income back below a phase-out threshold. This is not a small adjustment: a $70,000 Solo 401(k) contribution in the right year can mean keeping a five-figure deduction you would otherwise lose.

Entity structure. An LLC taxed as a sole proprietor with strong profits and no payroll may be leaving the W-2 wage limitation on the table. An S-corp election, sized with a reasonable salary, can create W-2 wages that unlock a larger deduction. The calculus includes payroll-tax costs and administrative overhead, so it does not always pencil out, but it often does, and most owners have never run the numbers.

Income timing. Business owners have more flexibility over when income is recognized than employees do. Accelerating deductible expenses, deferring a year-end invoice, or timing a bonus can shift taxable income across a threshold year. This is where the Soil layer of a retirement plan, the tax-architecture layer, earns its keep, because decisions made in November shape a deduction claimed in April.

What to Do Before Year-End

Pull your projected 2026 taxable income now, not in December. Compare it against the current SSTB phase-out ranges your CPA confirms. If you are within $50,000 of a threshold, model the contribution and timing options before you close the books. The QBI deduction is not complicated to preserve once someone is actually watching for it.

If you want a second set of eyes on whether your current structure is capturing the full deduction, that conversation starts here.

The information provided is for educational purposes only and does not constitute investment, legal, or tax advice. Consult with qualified professionals for guidance specific to your situation.