A K-1 and a W-2 both report income to you and to the IRS, but they describe very different relationships with the money. A W-2 shows wages you earned as an employee, with income tax, Social Security, and Medicare already withheld from each paycheck. A Schedule K-1 shows your share of income from a business you partly own, with nothing withheld and the tax bill left entirely to you. That single difference between K-1 vs W-2 income drives everything else: when you pay, which taxes apply, what you can deduct, and when you can actually file your return.
Who Gets Which Form
A W-2 goes to employees. Your employer issues one whenever it withheld income tax, Social Security, or Medicare from your pay during the year.1Internal Revenue Service. About Form W-2, Wage and Tax Statement
A Schedule K-1 goes to owners. You receive one if you hold an interest in a partnership, an S corporation, or a multi-member LLC taxed as either. The partnership or LLC files Form 1065; the S corporation files Form 1120-S. Each of those returns generates a K-1 for every owner, showing that person’s share of the entity’s income, losses, deductions, and credits.2Internal Revenue Service. Instructions for Form 1065 (2025) – Schedules K and K-1 The business itself pays no federal income tax on that income. It passes through to the owners’ personal returns.
Trusts and estates also issue K-1s to beneficiaries under Form 1041, but the rest of this comparison focuses on the business K-1s that people usually mean when they ask about K-1 versus W-2 income.3Internal Revenue Service. Instructions for Schedule K-1 (Form 1041) for a Beneficiary Filing Form 1040 or 1040-SR
Withholding vs. Quarterly Estimated Payments
This is the difference most people feel first. On a W-2 job, your employer withholds federal income tax based on the Form W-4 you filed, plus Social Security and Medicare. By the time you see your paycheck, the IRS has already been paid. If too much came out, you get a refund; if too little, the balance due at filing is usually small.
K-1 income works nothing like that. Nobody withholds anything. The business sends the K-1 after the year ends, and you owe the tax yourself. The IRS expects quarterly estimated payments through Form 1040-ES.4Internal Revenue Service. Estimated Taxes For calendar-year filers, those payments fall on April 15, June 15, September 15, and January 15 of the following year.5Internal Revenue Service. Publication 509 (2026), Tax Calendars
The catch: you’re paying tax quarterly on income you can’t fully calculate yet. To avoid an underpayment penalty, you need to hit a safe harbor, either 90% of your current-year tax or 100% of last year’s tax (110% if your prior-year AGI exceeded $150,000).6Internal Revenue Service. 2026 Form 1040-ES, Estimated Tax for Individuals Most K-1 recipients lean on the prior-year figure because it’s the only number they can pin down.
One more thing to know before you sign up for a partnership stake: you owe tax on your share of the entity’s profit even if no cash was distributed to you. A partnership can retain all its earnings to fund growth, and your tax bill still comes.
FICA vs. Self-Employment Tax
Both W-2 employees and many K-1 recipients pay into Social Security and Medicare. The rate is the same. Who writes the check is not.
For employees, FICA totals 15.3%, split evenly with your employer: 6.2% each for Social Security, 1.45% each for Medicare.7Internal Revenue Service. Topic No. 751, Social Security and Medicare Withholding Rates Social Security applies to the first $184,500 of wages in 2026; Medicare has no cap.8Social Security Administration. Contribution and Benefit Base An additional 0.9% Medicare tax kicks in on wages above $200,000, with no employer match.
For general partners and LLC members, the equivalent is self-employment tax at the same 15.3% combined rate on their share of ordinary business income, except that you pay both halves.9Internal Revenue Service. Self-Employment Tax and Partners You can deduct half of the self-employment tax as an adjustment to gross income, which softens the blow.10Office of the Law Revision Counsel. 26 U.S. Code 1402 – Definitions
S corporation shareholders get a real break here. Ordinary business income on an S-corp K-1 is not subject to self-employment tax.11Internal Revenue Service. Shareholder’s Instructions for Schedule K-1 (Form 1120-S) (2025) That’s a major reason people choose the S-corp structure. The catch is that if you actively work in the business, the IRS requires the corporation to pay you a reasonable salary reported on a W-2, and FICA applies to that salary in the normal way.12Internal Revenue Service. S Corporation Compensation and Medical Insurance Issues Only the profit above that reasonable salary flows through the K-1 free of employment taxes.
The benefits side matters too. Only income subject to FICA or self-employment tax earns Social Security credits. W-2 wages count. Partnership K-1 income subject to self-employment tax counts. S-corp K-1 distributions that skip self-employment tax don’t count, so an S-corp owner who takes a small salary and large distributions can end up with gaps in their Social Security record. In 2026 you need $1,890 in covered earnings for one credit, and 40 credits to qualify for retirement benefits.13Social Security Administration. Quarter of Coverage
What Kind of Income Each Form Reports
A W-2 is a single bucket. Box 1 shows your total taxable wages, tips, and other compensation, all of it earned income taxed at ordinary rates. Other boxes report withholding, 401(k) contributions, employer-sponsored health coverage, and similar items, but the income itself is one type.
A K-1 is different because a pass-through entity can earn many kinds of income, and each type keeps its tax character on the way to your return. Ordinary business income sits in one box. Rental income, interest, dividends, and capital gains each get their own. Ordinary business income and rental income from the K-1 flow to Schedule E; capital gains flow to Schedule D.14Internal Revenue Service. About Schedule E (Form 1040), Supplemental Income and Loss15Internal Revenue Service. Schedule D (Form 1040) Long-term capital gains keep their preferential rate. If the K-1 lumped everything together, you’d lose that.
K-1 income also carries passive-activity labels. If you don’t materially participate in the business, your share of its income or loss is generally passive, and passive losses can only offset passive income, not your wages. Rental activities are usually treated as passive regardless of participation, which is a common surprise for real estate investors who assumed rental losses would offset a W-2 salary.
The 20% Qualified Business Income Deduction
One of the biggest advantages of K-1 income over W-2 income is the qualified business income deduction under Section 199A, which lets eligible owners deduct up to 20% of their qualified pass-through income.16Internal Revenue Service. Qualified Business Income Deduction The One Big Beautiful Bill Act made this deduction permanent starting in 2026 and widened the phase-out range for joint filers.
W-2 wages are explicitly excluded. So is reasonable compensation an S corporation pays its shareholder-employee, and so are guaranteed payments from a partnership.16Internal Revenue Service. Qualified Business Income Deduction Only the pass-through profit itself qualifies.
Below roughly $200,000 of taxable income (single) or $400,000 (married filing jointly) for 2026, the deduction is straightforward. Above those thresholds, limitations phase in based on the type of business, the W-2 wages the business pays, and the cost basis of its property. Certain service businesses like law, medicine, and consulting face stricter limits and lose the deduction entirely at higher incomes. For owners under the threshold, though, this deduction can meaningfully cut the tax on K-1 income, and W-2 earners have no equivalent.
The Net Investment Income Tax
Higher-income K-1 recipients also face a 3.8% net investment income tax that generally doesn’t reach W-2 wages. It applies to the lesser of your net investment income or the amount your modified adjusted gross income exceeds $200,000 (single) or $250,000 (married filing jointly).17Internal Revenue Service. Topic No. 559, Net Investment Income Tax
Passive K-1 income counts as net investment income. A silent partner drawing distributions from a partnership could face ordinary income tax, self-employment tax if they’re a general partner, and the 3.8% surtax on top. W-2 wages are never subject to this tax, though they do count toward the income threshold that triggers it.
When Each Form Arrives
Employers must furnish W-2s by January 31.18Social Security Administration. Deadline Dates to File W-2s That leaves most employees ready to file well before April 15.
K-1 recipients rarely have that luxury. Partnership and S-corp returns aren’t due until March 15, and many entities file for an automatic six-month extension to September 15. The K-1 arrives whenever the entity finishes.5Internal Revenue Service. Publication 509 (2026), Tax Calendars So K-1 recipients routinely file their own extension to October 15, while still owing any tax by April 15. Many end up overpaying in April to stay safe and truing up later when the K-1 finalizes.
If Your K-1 Is Late or Wrong
If a K-1 still hasn’t arrived by the time you need to file, you can estimate the amounts from the best information available. If the entity hasn’t filed at all, attach Form 8082 to notify the IRS that no K-1 was received and that you’re reporting the items as best you can.19Internal Revenue Service. Instructions for Form 8082
Form 8082 also covers a K-1 you believe is incorrect. Report what you think the right numbers are, explain the discrepancy, and attach the form. Skip this step and the risk is on you: if the IRS later disagrees with the entity’s return, any resulting tax deficiency and penalties can be assessed against you directly.19Internal Revenue Service. Instructions for Form 8082
When You Get Both a W-2 and a K-1
Plenty of people get both forms, and in some structures that’s exactly how it’s meant to work. The clearest example is an S corporation shareholder who works in the business. The IRS requires a reasonable salary, which the company reports on a W-2 with normal FICA withholding, while the remaining profit flows through on a K-1 without self-employment tax.12Internal Revenue Service. S Corporation Compensation and Medical Insurance Issues
Health insurance adds a wrinkle. If you own more than 2% of an S corporation, premiums the company pays on your behalf get reported as wages in Box 1 of your W-2, though not in the Social Security and Medicare wage boxes. That lets you claim an above-the-line deduction for the premiums on your personal return.12Internal Revenue Service. S Corporation Compensation and Medical Insurance Issues Getting this reporting wrong is one of the more common S-corp compliance errors.
The other common combination is a W-2 from one employer and a K-1 from an unrelated investment, like a limited-partner stake in a real estate fund. Each form follows its own rules. The W-2 income already has tax withheld; the K-1 income needs quarterly estimates or additional withholding through an adjusted W-4 at the day job to cover the extra liability.