If you own an S-corporation, LLC, partnership, or sole proprietorship, the Section 199A Qualified Business Income (QBI) deduction can shave up to 20 percent off your business income before you ever calculate tax. For seven years, the deduction lived under a December 31, 2025 sunset clause — meaning every tax planner was bracing for the cliff. Then the One Big Beautiful Bill Act (OBBBA), signed into law on July 4, 2025, made the deduction permanent and added a small-business floor that kicks in starting this tax year.
For pass-through owners running anything from a freelance design shop to a multi-state HVAC company, Section 199A is often the single largest deduction on the return. Here is what changed, what stayed the same, and how to actually compute the deduction for tax year 2026.
What Section 199A Actually Does
Section 199A of the Internal Revenue Code allows owners of pass-through entities to deduct up to 20 percent of their Qualified Business Income from federal taxable income. Eligible entities include:
- Sole proprietorships filing Schedule C
- Single-member LLCs (disregarded entities) filing Schedule C or E
- Multi-member LLCs and partnerships passing income through K-1s
- S-corporations passing income through K-1s
- Certain trusts and estates with pass-through business income
A few important boundary rules:
- The deduction is available whether you itemize or take the standard deduction.
- It is a below-the-line deduction — it reduces taxable income but not adjusted gross income.
- It does not reduce self-employment tax. SE tax is computed on Schedule SE net earnings before any QBI adjustment.
- C-corporations are excluded. They received the flat 21 percent corporate rate under TCJA instead.
- Employees cannot claim it on W-2 wages. Statutory employees, however, can.
The deduction also covers 20 percent of qualified REIT dividends (reported in Box 5 of Form 1099-DIV) and qualified publicly traded partnership (PTP) income, even if you have no operating business.
What Counts as Qualified Business Income
QBI is the net amount of qualified items of income, gain, deduction, and loss from any qualified trade or business that operates in the United States. It includes:
- Schedule C net income from sole proprietorships
- Schedule E rental real estate income that rises to the level of a "trade or business" (see the Rev. Proc. 2019-38 safe harbor, which generally requires 250 hours of rental services per year)
- K-1 ordinary income from partnerships and S-corporations
QBI explicitly excludes:
- Capital gains and losses (short or long term)
- Dividends, interest income not allocable to the business, and annuity income
- Reasonable compensation paid to S-corporation owner-employees (this is wages, not QBI)
- Guaranteed payments to partners for services rendered
- Foreign-source business income
- Investment-type items even if the LLC happens to be the holder
The reasonable compensation exclusion is the one that catches most S-corp owners off guard. Every dollar you pay yourself on a W-2 is a dollar that does not feed the QBI calculation. We will come back to this trade-off below.
The 2026 Taxable Income Thresholds
Section 199A's complexity scales with income. Below the first threshold, the calculation is simple: 20 percent of QBI, capped by 20 percent of taxable income minus net capital gains. Above the threshold, the W-2 wage limit, the UBIA limit, and the SSTB phase-out all come into play.
For tax year 2026, the phase-in begins at:
- $201,750 for single, head of household, and married filing separately
- $403,500 for married filing jointly
The phase-in completes at:
- $276,750 for single, HOH, and MFS (a $75,000 phase-in range)
- $553,500 for MFJ (a $150,000 phase-in range)
OBBBA expanded these bandwidths from $50,000/$100,000 to $75,000/$150,000 starting in 2026, which makes the cliff less sudden and gives planners more room to maneuver in the middle band.
The W-2 Wages and UBIA Limitation
For non-SSTB businesses where taxable income exceeds the upper phase-in completion threshold, the QBI deduction for each trade or business is capped at the greater of:
- 50 percent of the W-2 wages paid by the business, or
- 25 percent of the W-2 wages plus 2.5 percent of the unadjusted basis immediately after acquisition (UBIA) of qualified property.
UBIA is essentially the original cost basis of depreciable tangible property still inside its "depreciable period," which is 10 years or the MACRS recovery period of the property, whichever is longer. UBIA does not decline with depreciation — it stays at the original cost for the full UBIA period.
The two-prong test rewards different business models. A labor-heavy business like a software development shop will easily satisfy the 50 percent W-2 wages prong. A capital-intensive business like a self-storage facility or a real estate rental might have minimal W-2 wages but substantial UBIA in the buildings and equipment — the second prong is built for them.
Example: How the W-2 Limit Plays Out
Suppose a married couple owns an S-corporation manufacturer with $500,000 of QBI. Their taxable income is $700,000 — well above the $553,500 phase-in completion. They pay $180,000 in W-2 wages and have $400,000 of UBIA in machinery.
- 20% of QBI: $100,000
- 50% of W-2 wages: $90,000
- 25% of W-2 wages plus 2.5% of UBIA: $45,000 + $10,000 = $55,000
The deduction is capped at $90,000 (the greater of the two limit prongs), and then taken if less than 20 percent of QBI. The owners take $90,000.
The SSTB Phase-Out
Specified Service Trade or Business (SSTB) is the trickiest concept in Section 199A. An SSTB is any trade or business in the fields of:
- Health — doctors, dentists, veterinarians, pharmacists, nurses, physical therapists, chiropractors, psychologists
- Law — lawyers, paralegals operating as principals
- Accounting — CPAs, EAs, bookkeepers, tax preparers
- Actuarial science
- Performing arts — actors, musicians, dancers
- Consulting — anyone providing professional advice and counsel
- Athletics — athletes, coaches, team operators
- Financial services — wealth management, retirement planning, M&A advisory, valuation
- Brokerage services — securities brokers
- Investing and investment management
- Trading or dealing in securities, partnership interests, or commodities
- Any trade or business where the principal asset is the reputation or skill of one or more employees or owners
Notably NOT classified as SSTBs: real estate brokerage, insurance brokerage, banking, architecture, and engineering. These exclusions were carved out specifically in the TCJA negotiations and remain intact.
For SSTB owners:
- Below the lower threshold: full 20 percent deduction
- Within the phase-in range: deduction reduces proportionally as both QBI and the W-2/UBIA limit are scaled down
- Above the upper threshold: deduction is completely eliminated
This is the "doctor cliff" — a married physician earning $600,000 in 2026 receives zero QBI deduction on practice income because the SSTB phase-out has fully eliminated it.
The "Crack and Pack" Trap
Early after TCJA, some advisors recommended splitting an SSTB into an "operating" SSTB and a non-SSTB ancillary business (rental real estate, equipment leasing, administrative services) to shelter income from the SSTB phase-out. The Section 199A final regulations shut this down with the SSTB attribution rules — if 50 percent or more of an otherwise non-SSTB business's gross receipts come from a related SSTB, the non-SSTB is treated as part of the SSTB for the entire trade or business. Plan around this rule, not against it.
The New $400 Minimum Deduction (Starting 2026)
OBBBA added a new minimum deduction. Starting in tax year 2026, a taxpayer with at least $1,000 of total QBI from one or more active qualified trades or businesses is statutorily entitled to claim a minimum QBI deduction of $400, regardless of other limitations. Both the $1,000 trigger and $400 floor will be inflation-adjusted in years after 2026.
The minimum protects very small pass-through earners — think a part-time freelance writer with $1,500 of net Schedule C income — from being fully cut off by other limitations. For most readers of this article, the minimum will not matter; the 20 percent standard calculation will produce a larger number. But it is now a backstop that exists.
Aggregation Rules — A Powerful Planning Lever
Section 199A allows taxpayers to aggregate multiple trades or businesses for the purposes of the W-2 wages and UBIA tests, provided five conditions are met:
- The same person or group owns at least 50 percent of each business
- Ownership exists for the majority of the tax year (or whole year, depending on the specific rule)
- All businesses share the same tax year
- None of the businesses is an SSTB
- The businesses meet two of three factors: they offer similar products or services, they share facilities or workforce, or they operate in coordination with each other
A classic aggregation play: an S-corporation runs a manufacturing operation and pays substantial W-2 wages. A sister S-corporation owns the real estate, rented to the operating company on a triple-net lease. Without aggregation, the real estate rental has zero W-2 wages and may produce a small deduction (limited by the 2.5% UBIA test). With aggregation, the manufacturing W-2 wages support the rental's QBI, and the combined deduction often grows materially.
Aggregation is elected on Form 8995-A Schedule B, and it is sticky — once made, the election must be maintained in subsequent years unless circumstances materially change (such as a sale of one of the aggregated businesses).
Form 8995 vs. Form 8995-A
Two forms exist:
- Form 8995 (Qualified Business Income Deduction Simplified Computation): use this if taxable income before the QBI deduction is at or below the threshold AND you are not a patron of an agricultural or horticultural cooperative.
- Form 8995-A (Qualified Business Income Deduction): use this if taxable income exceeds the threshold, if you own SSTB interests, if you elect to aggregate businesses, or if you have agricultural cooperative patron income.
If you claim a QBI deduction but skip the form, the IRS denies the deduction. Returns with bare QBI deductions and no attached form are commonly bounced back with a CP2000 notice and a recomputed tax bill.
Planning Strategies for Pass-Through Owners
1. Manage Taxable Income Around the Threshold
Look at projected taxable income in November or December. If you are $20,000 over the SSTB phase-in completion as a consultant, can you accelerate retirement plan contributions, increase HSA contributions, defer a large client invoice into January, or harvest capital losses? Every dollar of taxable income reduction below the threshold restores QBI deduction value.
2. Tune S-Corp Reasonable Compensation Carefully
S-corp owners face a structural tension. Higher W-2 wages to the owner-employee reduce QBI (since owner W-2 wages are not QBI). But they also raise the W-2 wage limitation cap for non-SSTB businesses. There is a sweet spot. A common rule of thumb when income is above the threshold and you are bumping against the W-2 wages cliff: paying yourself roughly 28 to 29 percent of net business income as W-2 wages tends to maximize the combined federal tax savings. Reasonable compensation must still meet IRS facts-and-circumstances scrutiny, however, so do not engineer a number that has no relationship to the work performed.
3. Bunch Equipment Purchases for UBIA
A real estate, manufacturing, or contracting business hitting the W-2 wages cliff can use Section 179 and bonus depreciation to keep UBIA on the books while accelerating cash deductions. Bonus depreciation expenses the property immediately, but UBIA persists at original cost for the full UBIA period, supporting the 2.5 percent prong of the limitation.
4. Aggregate Real Estate With the Operating Business
If you own the building your S-corp operates from in a separate LLC, aggregation often unlocks materially more QBI deduction. File Form 8995-A Schedule B every year you wish to maintain aggregation, and make sure ownership and the qualifying factors continue to hold.
5. Watch State Conformity
Most states do not conform to Section 199A. Your state taxable income may not reflect the federal QBI deduction, which means state tax planning runs on a separate track. A few states (notably some PTET regimes) have created their own pass-through workarounds — coordinate with a local advisor.
Bookkeeping You Need to Compute Section 199A Correctly
Section 199A is not something you can backfill at tax time from a year of messy records. Accurate, real-time bookkeeping is non-negotiable for QBI optimization. At minimum, you need:
- Trade-or-business segregation in your chart of accounts — one income statement per qualified trade or business
- A W-2 wage subledger by entity, reconcilable to each entity's Form W-3 Box 1 and Box 5 totals
- A fixed asset register showing original cost, placed-in-service date, depreciation method, and the remaining UBIA period
- Clean separation between owner W-2 wages, guaranteed payments, distributions, and contributions
- REIT dividend tracking on brokerage 1099-DIV Box 5 (Section 199A dividends) so they can be added to the calculation
- For rental real estate claiming the Rev. Proc. 2019-38 safe harbor, contemporaneous time logs of the 250 rental services hours
Without these subledgers, your CPA cannot confidently complete Form 8995-A, and you will end up either under-claiming the deduction or exposing yourself to IRS adjustment on examination.
Common Mistakes to Avoid
- Treating S-corp distributions as QBI. Distributions are not income items; the K-1 ordinary income flowing to Box 1 is the QBI source.
- Counting reasonable compensation as QBI. Owner W-2 wages reduce QBI; they do not contribute to it.
- Forgetting the overall taxable income cap. The deduction is limited to 20 percent of taxable income minus net capital gains. If you have large capital gains, your QBI ceiling can be lower than 20 percent of QBI itself.
- Skipping Form 8995 or 8995-A. Without the form, the IRS denies the deduction entirely.
- Mixing SSTB and non-SSTB activities under one entity. A single business has a single classification — usually the whole entity falls into the SSTB bucket if a meaningful share of receipts come from the specified service.
- Failing to elect aggregation when it helps. Aggregation is opt-in. If you do not file Schedule B, you do not get the benefit, even if you would have qualified.
Keep Your Financial Records Organized for Smarter Tax Planning
Section 199A planning, like every other modern tax move, rewards businesses that keep clean, transparent books year-round. The owners who maximize their QBI deduction are the ones who can pull a clean trial balance by qualified trade or business in seconds, not the ones scrambling through a shoebox of receipts in March. Beancount.io offers plain-text accounting that gives you complete transparency and control over your financial data — version-controlled, auditable, and AI-ready, with no black boxes and no vendor lock-in. Get started for free and see why developers, finance professionals, and pass-through owners are switching to plain-text accounting.