A K-1 lands on your desk showing $80,000 ordinary business income, $4,000 interest, $6,000 qualified dividends, $15,000 long-term capital gain, and a $20,000 §179 deduction. None of these flow to one place on Form 1040. Each line has a specific destination, and the QBI deduction on top depends on which numbers landed where.
Partnerships, S corporations, and trusts pay no entity-level federal income tax in most cases. Congress designed these structures to tax the economic owners directly, in the year the entity earns the income, regardless of whether cash is distributed. The K-1 pushes each owner's share of every income, deduction, and credit item to the individual return.
KEY: Pass-through income is taxable whether or not cash is distributed. A partner with $100,000 of K-1 ordinary income owes tax on $100,000 even if the partnership distributed nothing.
Schedule K-1 (Form 1065): Partnerships and LLCs. Issued by general partnerships, limited partnerships, and multi-member LLCs taxed as partnerships. Reports each partner's distributive share per the partnership agreement.
Common mistakes
- Treating pass-through income as cash-driven. A partner with $80,000 of K-1 ordinary income but 0 (or just the cash distributed). The K-1 number is the taxable amount.
- Routing all K-1 lines to Schedule E. Only ordinary business income, rental income, and royalties land on Schedule E. Interest goes to Schedule B, dividends to Schedule B, capital gains to Schedule D, charitable contributions to Schedule A. Lumping everything onto Schedule E is the most common form-mapping error.
- Treating S-corp salary as QBI. Reasonable compensation paid as W-2 wages to an S-corp shareholder is NOT QBI. Only K-1 ordinary business income is QBI. Including the salary inflates the §199A deduction.
Bottom line
- Schedule K-1 reports your share of pass-through items: Form 1065 K-1 from partnerships, Form 1120-S K-1 from S corps, Form 1041 K-1 from trusts and estates.
- Each K-1 line lands on the schedule the owner would use directly: ordinary business income to Schedule E Part II, interest and dividends to Schedule B, capital gains to Schedule D, charitable contributions to Schedule A. Character is preserved.
- Pass-through income is taxable regardless of distribution; the K-1 number drives recognition, not cash flow.
- §179 is computed at the entity level for dollar caps but applied at the owner level subject to the owner's own taxable-income limit.
Exam shortcut
When a problem hands you a K-1, map each box to its target schedule before computing anything. The trap answer parks investment income on Schedule E with the ordinary income. Map first, math second. For QBI, isolate the K-1 ordinary business income line, that is the only candidate. For S-corp basis, the question almost always asks whether a guarantee creates basis. The answer is no.
The full lesson (about 2,618 words, 17 min read) adds 2 worked examples, all 6 common mistakes, a self-check, free in the app.
Learning objectives
- IV.B1
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