Specified Service Trade or Business

Why the rule exists

The 2017 law cut the corporate rate to 21% and, so that a plumber organized as an S corporation was not left paying far more than a plumber organized as a corporation, gave pass-through owners a 20% deduction on business income. Congress did not want the deduction to become a way for a well-paid professional to relabel salary as business profit, so it carved out the fields where the income is really the owner’s own labor — and then limited the carve-out to people above an income threshold. Below the threshold, a doctor and a contractor get the same deduction. Above it, they do not.

Who is on the list

A specified service trade or business is one in the fields of:

• Health — physicians, dentists, pharmacists, nurses, veterinarians, physical therapists, psychologists and other providers of medical services. Not a health club, not a medical device maker, not a billing company.
• Law — lawyers, paralegals, mediators. Not the court reporter or the process server.
• Accounting — accountants, enrolled agents, return preparers, auditors, bookkeepers. This office is a specified service business.
• Actuarial science.
• Performing arts — actors, musicians, singers, directors. Not the sound engineer or the venue.
• Consulting — professional advice and counsel, including lobbying. Not advice that comes bundled with the sale of goods or other services and is not billed separately.
• Athletics — athletes, coaches, team managers. Not the stadium operator or the broadcaster.
• Financial services — financial advisers, wealth managers, retirement planners, investment bankers. Not a bank taking deposits and making loans.
• Brokerage services — stockbrokers. Expressly not real estate agents and brokers, and not insurance agents and brokers.
• Investing and investment management, trading, and dealing in securities, partnership interests or commodities.
• Any business whose principal asset is the reputation or skill of its owners or employees. This sounds like it could sweep in every skilled tradesman, and when the law passed many people feared it would. The regulations narrowed it to three things: being paid to endorse products, licensing your name or likeness, and appearance fees. A chef with a famous name who runs a restaurant is not caught; the same chef paid to endorse a brand of cookware is, for that income.

Expressly not on the list: engineering, architecture, real estate brokerage, property management, insurance sales, banking — and every trade, retailer, manufacturer, restaurant and landlord.

How it bites

• Below the threshold: the full 20% deduction, specified service or not. Most small practices are here.
• In the phase-in range: the deduction shrinks on a straight line. In 2025 the range is $50,000 above the threshold ($100,000 joint); from 2026 it is $75,000 ($150,000 joint), which lets more income through.
• Above the range: none of the business’s income counts. The deduction is zero for that business, whatever wages it pays and whatever property it owns. (A non-service business above the range keeps a deduction limited by its wages and property; a service business gets nothing.)
• The threshold is measured by the owner’s taxable income, not the business’s profit. An S corporation with three dentist-owners may produce the deduction for one and not the others.

For a single dentist, lawyer or consultant with taxable income around $260,000 in 2025, the deduction was already gone; in 2026 the same income is inside the wider range and some of it survives. The 2025 law’s widening of the range is worth real money to professionals in exactly that band.

Three rules that catch people

• The de minimis rule. A business that does a little specified-service work is not tainted: under $25 million in receipts, less than 10% of receipts from the service activity is fine (5% above $25 million). But it is a cliff. At 11%, the whole business is a specified service, unless the two activities are run as separate businesses with separate books.
• The self-rental trap. If you own the building your practice rents, the rent you collect is treated as specified-service income too, because the rental and the practice are under common control. The dentist who owns her office cannot shelter the rent from the rule by putting it in a separate LLC.
• Once a specified service, always separate. A specified service business cannot be combined with other businesses to share wages or property for the deduction calculation.

What can be done

Less than the seminars suggest. The rule turns on taxable income, so anything that lowers taxable income in a year near the threshold — a larger retirement plan contribution, a health savings account, timing of income and deductions, the choice between S corporation salary and distributions — can bring part of the deduction back. A genuinely separate line of business with its own books may qualify on its own. Restructuring a practice to make it look like something it is not does not work and is the kind of thing examiners look for.

The honest answer for most professionals above the range is that the deduction is simply not available to them, and the planning conversation is about the other things that are. That is our self-employed page under Tax Aversion Therapies.

Where this came from

Section 199A was part of the Tax Cuts and Jobs Act of 2017. The specified-service list borrows from a 1993 provision on small business stock, with engineering and architecture removed. The regulations defining each field were proposed in August 2018 and finalized in early 2019; the 2025 law made the deduction permanent and widened the phase-in. The deduction itself is covered on our QBI page.