A sole proprietor operates a specified service trade or business (SSTB), such as a consulting practice, and for the 2025 U.S. federal tax year the proprietor's taxable income is well above the SSTB phase-out range. Under IRC Section 199A, what is the effect on the qualified business income (QBI) deduction for that business?
- The 20% QBI deduction is still available in full because the SSTB restriction under Section 199A applies only to C corporations, not to sole proprietors
- The deduction is limited to the greater of 50% of W-2 wages, or 25% of W-2 wages plus 2.5% of qualified property — the wage-and-property limitation that applies to non-SSTB businesses at high income
- The deduction converts automatically into a below-the-line itemized deduction once taxable income exceeds the SSTB phase-out range
- The QBI deduction from the SSTB is reduced to zero, because once taxable income is above the phase-out range, income from a specified service trade or business no longer qualifies for the deduction at all
Why D? And why not the others?
Correct answer: D. The QBI deduction from the SSTB is reduced to zero, because once taxable income is above the phase-out range, income from a specified service trade or business no longer qualifies for the deduction at all
Under IRC Section 199A, once a taxpayer's taxable income rises above the SSTB phase-out range entirely, income from a specified service trade or business no longer qualifies for the QBI deduction at all — the deduction for that business's income drops to zero, regardless of how much the business pays in W-2 wages or holds in qualified property. The option describing a wage-and-property limitation of the greater of 50% of W-2 wages, or 25% of W-2 wages plus 2.5% of qualified property, is wrong for an SSTB above the phase-out range: that limitation is what applies to a non-SSTB business at high income, which keeps some deduction if it pays enough wages or holds enough qualified property, unlike an SSTB, which loses the deduction outright. The option restricting the SSTB rule to C corporations is wrong because Section 199A's SSTB restriction applies to any pass-through structure carrying on the business, including sole proprietorships, partnerships, and S corporations; C corporations are not eligible for the QBI deduction in the first place, so the restriction would be meaningless applied there. The option describing an automatic conversion into a below-the-line itemized deduction is wrong because no such conversion mechanism exists — the deduction simply disappears for SSTB income above the range rather than changing form.
Source: IRS, 'Qualified Business Income Deduction' (irs.gov/credits-deductions/individuals/qualified-business-income-deduction); IRS Rev. Proc. 2024-40 (2025 Section 199A thresholds)