Strategy Snapshot
Section 199A gives most owners of sole proprietorships, partnerships, and S-corps a deduction of up to 20% of their qualified business income. Below the income thresholds it is nearly automatic. Above them, the W-2 wage limit and the service-business restriction decide whether you keep the full deduction or lose it.
A deduction of up to 20% of qualified business income, taken on your personal return whether or not you itemize. On $200,000 of profit, that is up to $40,000 off taxable income.
Below the taxable-income threshold (about $197,300 single / $394,600 joint for 2025), the deduction is simple. Above it, the W-2 wage and property limits and the service-business rules kick in.
For high earners over the threshold, paying W-2 wages, including a reasonable S-corp salary, can be what unlocks or preserves the deduction.
The qualified business income deduction is the most valuable write-off many business owners never claim correctly. It lets most pass-through owners deduct 20% of their business profit before calculating tax, and unlike most deductions, you get it whether you itemize or take the standard deduction. On a healthy profit, that is real money, and the 2025 tax law made it permanent, so it is now a planning fixture rather than a temporary perk.
On $200,000 of qualified business income, the Section 199A deduction can knock up to $40,000 off your taxable income, before you do anything else.What it is worth
What Qualifies
The deduction under Section 199A applies to qualified business income from pass-through businesses:
- Sole proprietorships (Schedule C)
- Single-member LLCs
- Partnerships and multi-member LLCs
- S-corporations
- Some REIT dividends and publicly traded partnership income
QBI is your net business profit from U.S. operations. It does not include W-2 wages you pay yourself, guaranteed payments, investment income (interest, dividends, capital gains), or income earned outside the United States.
The Income Threshold Changes Everything
Whether the deduction is simple or complicated depends on one number: your taxable income.
Above those thresholds (which adjust for inflation annually), two sets of limits phase in over a range. The 2025 tax law widened that phase-in range starting in 2026, giving more breathing room before the limits bite fully.
The Two Limits for Higher Earners
Once you are over the threshold, the rules split based on what kind of business you run.
1. The specified service business (SSTB) restriction. If your business is a specified service trade or business, the deduction phases out completely above the range. SSTBs include businesses where the principal asset is the reputation or skill of its owners or employees:
- Health, law, accounting, and consulting
- Financial services, brokerage, and investment management
- Performing arts and athletics
Notably, engineering and architecture are excluded from the SSTB list, and so are most product, software, and real estate businesses.
2. The W-2 wage and property limit. For non-service businesses over the threshold, the deduction is capped at the greater of:
- 50% of the business’s W-2 wages, or
- 25% of W-2 wages plus 2.5% of the unadjusted basis of qualified property (UBIA)
| Your situation | What governs your deduction |
|---|---|
| Taxable income below threshold | Flat 20% of QBI, no other tests |
| Above threshold, non-service business | Greater of the two W-2 wage / property limits |
| Above threshold, service business (SSTB) | Deduction phases out to zero |
Why the S-Corp Salary Question Gets Interesting
For S-corp owners over the income threshold, the reasonable salary decision now does double duty. A W-2 salary reduces the income eligible for the 20% deduction, but it also creates the W-2 wages the limit requires. Set the salary too low and you may fail the wage test and lose the deduction; set it too high and you give back deduction on the salary itself.
The Overall Cap
One more limit applies to everyone: the total QBI deduction cannot exceed 20% of your taxable income minus net capital gains. In a year with large investment gains or low business income, this overall cap can quietly reduce the deduction below 20% of QBI.
The 2025 law also added a minimum deduction (starting at $400, inflation indexed) for taxpayers with at least $1,000 of QBI from an active business, a small floor that helps the smallest operators.
When to Seek Help
If your income is comfortably below the threshold, the deduction is largely mechanical and your software should handle it, though it is worth confirming you are actually getting it. The value of advice climbs sharply when your income is near or above the threshold, when you run a service business, when you have an S-corp salary to tune, or when you own multiple businesses that can be aggregated. Those are the situations where the difference between a default calculation and a planned one is measured in thousands of dollars a year, every year, now that the deduction is permanent.
Last updated: 2026