The 20% deduction most owners have never heard of

Most business owners know the small deductions: mileage, a home office, the occasional software subscription. Far fewer have heard of the one that can knock up to 20% off their business income before they even start counting write-offs. It's called the qualified business income deduction, or QBID, and it exists specifically for people running sole proprietorships, partnerships, S corps, and LLCs. If you're one of them, there's a real chance you're eligible and don't know it.

Here's what it is, who qualifies, and where the rules get more complicated as your income grows.

What the QBI deduction does

If your business is a sole proprietorship, partnership, S corp, or LLC taxed as one of those, you may be able to deduct up to 20% of your qualified business income. For partnerships and S corps, the deduction applies at the partner or shareholder level, on your personal return, not the business return.

A few things make this deduction unusual. It reduces your taxable income, not your adjusted gross income, which means it comes off after most other calculations. It doesn't reduce your self-employment tax; you still pay SE tax on the full amount of your net earnings. And you don't have to itemize to claim it. Whether you take the standard deduction or itemize, the QBID is still available.

The business also has to be conducted within the United States. Rental real estate is a special case we cover in a companion post, since income reported on Schedule E generally doesn't qualify unless you're operating it as a real estate business.

What counts as qualified business income

QBI is calculated separately for each trade or business you own, and it includes the income, gains, deductions, and losses connected to that business. That covers things like the deductible half of your self-employment tax, your self-employed health insurance deduction, and contributions to a qualified retirement plan, as long as they're tied to the business.

QBI does not include everything that shows up on your return. Wage income, capital gains and losses, dividends, interest income, reasonable compensation paid to yourself from an S corp, and guaranteed payments to partners are all excluded. If your business shows a loss for the year, that loss carries forward and reduces next year's deduction instead of disappearing.

The 2026 income thresholds

Below a certain income level, the QBID is straightforward: 20% of your qualified business income, no extra math required. Above that level, limitations start to phase in based on your filing status and taxable income.

Under the threshold, no limitation applies at all. Inside the phase-in range, a wage and property limit starts to apply gradually. Above the top of the range, that limit applies in full, and if your business is a specified service trade or business, the deduction disappears entirely. We've put this table, along with the wage and property formula below, on a single printable page if you'd rather keep it on your desk than scroll back to this post every time.

The wage and property limit

Once your taxable income is at least $75,000 above the threshold ($150,000 if you're married filing jointly), your 20% deduction gets capped by what's called the Form W-2 wages and qualifying property limit. Instead of just taking 20% of your business income, your deduction can't exceed the greater of:

• 50% of the W-2 wages your business paid, or
• 25% of W-2 wages paid, plus 2.5% of the unadjusted basis of the qualifying property your business owns.

In plain terms: businesses with employees on payroll, or businesses that own significant equipment or property, tend to fare better under this limit than businesses that are mostly the owner's own labor with little overhead.

Example: Mike runs a sole proprietorship making beef jerky. His qualified business income for 2026 is $180,000, and his taxable income is $280,000, which puts him above the phase-in range. He bought a $100,000 dehydrator during the year and paid one employee $20,000 in wages.

Mike's deduction is the lesser of 20% of his business income ($36,000) or his wage and property limit. That limit is the greater of 50% of wages ($10,000) or 25% of wages plus 2.5% of the dehydrator's cost ($5,000 + $2,500 = $7,500). The larger of those two figures is $10,000, so that's Mike's deduction: $10,000, not the $36,000 he'd get if his income were under the threshold.

When your business is a specified service trade or business

Some businesses face a harder cutoff. A specified service trade or business, or SSTB, includes fields like health, law, accounting, actuarial science, performing arts, consulting, athletics, and financial or brokerage services, along with anyone earning income from endorsements or the use of their name, image, or likeness. Architects and engineers are specifically excluded from this category, even though they're professional services.

If you're above the top of the phase-in range and your business is an SSTB, the deduction is disallowed entirely, not just limited. If you're inside the phase-in range, a percentage of your income gets excluded from QBI based on how far into the range you are.

Example: June is an attorney with taxable income of $210,600 and qualified business income of $153,000. Because her income is inside the phase-in range, her reduction is calculated as ($210,600 – $201,750) ÷ $75,000, which comes to 11.8%. Her QBI of $153,000 is reduced by $24,851, leaving $128,149. Her deduction is 20% of that, or $25,630, well short of the $30,600 she'd get without the SSTB limitation.

The minimum deduction floor

For 2026, the QBID can't be less than $400 after all limitations and phaseouts are applied, as long as you have at least some qualified business income for the year. It's a small detail, but it means the deduction doesn't fully disappear for lower-income owners the way it can for high-income SSTB owners above the threshold.

What about rental property?

If you own rental real estate, the default answer is that income reported on Schedule E doesn't qualify for the QBID because it's treated as investment income, not business income. There's a path around that: the IRS created a safe harbor that lets a rental real estate enterprise qualify if you meet specific hour and recordkeeping requirements. We break down exactly what that takes in a separate post.

Keep reading

A few other posts round out the picture on what you can deduct and how your structure affects it:

• Common deductions small business owners miss: the write-offs that quietly go unclaimed every year, from home office to Section 179.
• S Corp election: is it worth it?: how the S Corp election affects self-employment tax, and where it intersects with reasonable compensation and the QBID.
• The rental real estate safe harbor: how landlords can qualify for the QBI deduction what it takes to treat a rental property as a trade or business for QBID purposes.

Want this as a printable reference? We put the 2026 thresholds, the wage and property limit formula, and the SSTB rules on one page you can keep on your desk. Download the Qualified Business Income Deduction handout.

Not sure if you qualify?

A Vibe Check is a good place to start. We look at where you are and what needs attention, no judgment, just a clear picture of what to fix. Schedule yours here.

This post is for general informational purposes and doesn't constitute tax or legal advice. Qualifying for the QBI deduction, and how much of it you can claim, depends on your entity type, your income, and the specifics of your business. Talk to a tax professional before you file.