What Is a Specified Service Trade or Business (SSTB)?

A specified service trade or business, or SSTB, is a federal tax classification that limits or eliminates the 20% qualified business income (QBI) deduction under Section 199A of the Internal Revenue Code for owners of certain professional service businesses. If you’re a doctor, lawyer, accountant, consultant, financial advisor, or similar professional earning above set income thresholds, the SSTB label can cost you a deduction worth tens of thousands of dollars that other business owners keep. Below the thresholds, the classification doesn’t matter. Above them, it matters a great deal.

Which Businesses Count as SSTBs

The statute doesn’t spell out SSTB fields from scratch. It borrows the list from an older provision, Section 1202(e)(3)(A), and then carves out exceptions.¹ The regulations under Section 1.199A-5 then define what each field actually covers.² The fields are:

Health: physicians, dentists, nurses, pharmacists, veterinarians, physical therapists, psychologists, and similar providers. Gyms, health spas, and pharmaceutical manufacturers don’t count.
Law: lawyers, paralegals, arbitrators, and mediators. Support services like printing or stenography fall outside.
Accounting: accountants, enrolled agents, tax return preparers, and financial auditors.
Actuarial science: actuaries and similar risk professionals.
Performing arts: actors, singers, musicians, entertainers, and directors.
Consulting: professionals whose product is advice itself.
Athletics: professional athletes and others paid for athletic performance.
Financial and brokerage services: investment managers, securities traders, and those who arrange securities transactions for a fee.

The boundaries matter more than the labels. Consulting is narrower than most people assume: it applies only when advice itself is what you sell. A building contractor who advises clients on design choices during a project isn’t an SSTB on that account. Sales roles and training courses also sit outside the definition, even when marketed as consulting.

Fields the Statute Excludes

Engineering and architecture are specifically carved out. Section 199A points to the older list but instructs you to ignore the words “engineering, architecture.”¹ An architect earning $500,000 keeps the full QBI deduction; a lawyer at the same income gets nothing.

Real estate agents, real estate brokers, and insurance agents are also excluded. The IRS instructions for Form 8995-A clarify that “brokerage services” in this context means arranging securities transactions, not real estate or insurance transactions.³ The word sounds broad, but the tax definition is narrow.

The Reputation or Skill Category

A separate catch-all reaches businesses that trade on personal fame. The regulations limit it to three specific income types: endorsement fees, appearance fees, and payments for licensing your name, likeness, voice, signature, or trademark.² This is much narrower than early drafts suggested. A plumber with a great reputation doesn’t become an SSTB just because customers choose the business on word-of-mouth. The income has to fall into one of those three buckets.

When SSTB Status Actually Reduces Your Deduction

SSTB classification only matters if your taxable income before the QBI deduction crosses the income thresholds. Below them, you claim the full 20% deduction like any other business owner.⁴

The One Big Beautiful Bill Act, signed in 2025, made the Section 199A deduction permanent and widened the phase-in range where the SSTB limit kicks in. For the 2026 tax year:⁵

Single filers: phase-in begins at $201,750 and ends at $276,750.
Married filing jointly: phase-in begins at $403,500 and ends at $553,500.

The new ranges span $75,000 for single filers and $150,000 for joint filers, up from $50,000 and $100,000 through 2025. Those amounts continue to adjust for inflation.

How the Phase-In Reduction Works

The deduction doesn’t disappear all at once inside the phase-in range. The IRS calculates a reduction percentage based on how far your taxable income exceeds the lower threshold. For a single filer: take taxable income, subtract $201,750, divide by $75,000. The result is the percentage of your SSTB income excluded from the deduction.

Take a single attorney with $239,250 in taxable income. That’s $37,500 over the lower threshold. Divided by $75,000, the reduction percentage is 50%. If the attorney’s QBI is $180,000, half of it gets excluded, leaving $90,000 eligible and a deduction of $18,000 instead of the full $36,000. Once taxable income hits $276,750, the reduction reaches 100% and the SSTB deduction is gone.

A second limit applies to all QBI businesses, not just SSTBs: the deduction for each business can’t exceed the greater of 50% of W-2 wages the business paid, or 25% of W-2 wages plus 2.5% of the unadjusted basis of qualified property.¹ For a solo practitioner with no employees and no depreciable business property, both figures are zero, so this cap can eliminate the deduction even before the SSTB phase-out completes.

Mixed Revenue and the De Minimis Rule

A business earning both SSTB and non-SSTB revenue isn’t automatically an SSTB. The IRS provides a safe harbor tied to gross receipts from services:⁶

Gross receipts of $25 million or less: if less than 10% comes from specified services, the whole business escapes SSTB treatment.
Gross receipts above $25 million: the threshold drops to 5%.

The result is all-or-nothing. A technology company with $20 million in revenue that earns $1.9 million from consulting stays in the clear. Add another $200,000 in consulting fees and the entire $20 million becomes SSTB income. Businesses near the line need to track service revenue carefully.

You Can’t Split the Business to Escape

A common instinct is to peel off equipment, real estate, or administrative work into a separate entity to preserve the QBI deduction on that side. The regulations block it. If a business provides property or services to an SSTB and the two share 50% or more common ownership, the portion serving the related SSTB is itself treated as an SSTB.²

A dermatologist who creates a management company to handle billing, scheduling, and leasing won’t shield that income from the classification when both entities share common ownership. Common ownership follows the related-party rules of Sections 267(b) and 707(b), which reach family members and constructive ownership, so putting the second entity in a spouse’s or child’s name doesn’t help.

A rental real estate safe harbor under Revenue Procedure 2019-38 also excludes property rented to a commonly controlled business from its scope.⁷ A medical practice owner renting office space from a personally owned LLC won’t qualify that rental for the safe harbor.

SSTBs also cannot be included in aggregation groups for QBI purposes, which cuts off another common planning move where owners try to pool wages and property across businesses to prop up the deduction.⁸

Managing Income Around the Threshold

The most direct lever an SSTB owner has is taxable income itself, because the classification only bites above the threshold. Every dollar of taxable income you push down is a dollar that might keep you inside the phase-in range or below it.

Retirement plan contributions do the heaviest lifting. A self-employed professional using a solo 401(k) can defer up to $23,500 in elective contributions for 2025, with a $7,500 catch-up at age 50 or older, plus employer-side contributions up to 25% of net self-employment income. Health savings account contributions, charitable giving, and the timing of income and deductible expenses all shift where you land on the phase-in scale.

Filing status is itself a planning point: married filing jointly nearly doubles the threshold range. For a couple where one spouse runs an SSTB and the other runs a non-SSTB, keeping the two operations genuinely separate avoids the common-ownership problem, and the non-SSTB keeps its full deduction eligibility regardless of household income.

How to Report It, and What Happens If You Get It Wrong

The form you use depends on income. At or below $201,750 (single) or $403,500 (married filing jointly) for 2026, you use Form 8995, the simplified version. SSTB status is irrelevant at these levels, so the form doesn’t ask about it.⁴

Above those thresholds, you use Form 8995-A. Schedule A handles the SSTB-specific calculations, including the exclusion percentage applied to your qualified business income.⁹ For each business you’ll need three numbers: qualified business income, W-2 wages paid, and the unadjusted basis of qualified property immediately after acquisition. Owners of S corporations or partnerships get this information on Schedule K-1 under Code V in Box 17.¹⁰

The accuracy standard is stricter for QBI claims than for most other items. A “substantial understatement” of income tax normally triggers a 20% penalty when the understatement exceeds 10% of the correct tax or $5,000, whichever is greater. For taxpayers claiming the Section 199A deduction, that 10% figure drops to 5%.¹¹ A smaller error can trigger the penalty, and claiming the QBI deduction on income that should have been classified as SSTB income exposes you to 20% on top of the tax owed.¹² If your business sits near the edge of an SSTB category, document why you classified it the way you did before you file.

1
Office of the Law Revision Counsel. 26 USC 199A – Qualified Business Income
2
eCFR. 26 CFR 1.199A-5 – Specified Service Trades or Businesses and the Trade or Business of Performing Services as an Employee
3
Internal Revenue Service. Instructions for Form 8995-A
4
Internal Revenue Service. Instructions for Form 8995 (2025)
5
Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026, Including Amendments From the One Big Beautiful Bill
6
Internal Revenue Service. Instructions for Form 8995-A – Section: De Minimis Rule
7
Internal Revenue Service. Revenue Procedure 2019-38
8
eCFR. 26 CFR 1.199A-4 – Aggregation
9
Internal Revenue Service. Instructions for Form 8995-A (2025)
10
Internal Revenue Service. 2025 Shareholders Instructions for Schedule K-1 (Form 1120-S)
11
Office of the Law Revision Counsel. 26 USC 6662 – Imposition of Accuracy-Related Penalty on Underpayments
12
Internal Revenue Service. Accuracy-Related Penalty