Schedule K-1 boxes, explained simply: each box reports one share of an entity's income, deductions, credits or other items for one owner or beneficiary. The partnership (1065), S corporation (1120-S) and trust or estate (1041) versions use different numbering, so the same item can sit in different boxes. Lettered codes in a few boxes carry most of the detail.
Schedule K-1 boxes on the partnership Form 1065
The Schedule K-1 boxes on the partnership Form 1065 report a partner's share of the partnership's year in 23 numbered boxes, after two parts describing the partnership and the partner. Everything below refers to the 2025 form and the Partner's Instructions for Schedule K-1 (Form 1065) (2025).
Part I identifies the partnership: its EIN in item A, name and address in item B, and a check box in item D if it is a publicly traded partnership. Part II describes the partner. The items that get the most attention:
- Item J, the partner's share of profit, loss and capital, at the start and end of the year. The instructions say these percentages "are based on the partnership agreement."
- Item K1, the partner's share of liabilities, split into nonrecourse, qualified nonrecourse financing and recourse.
- Item L, the partner's capital account analysis, from beginning capital through contributions, income, withdrawals and ending capital.
- Items M and N, about contributed property with built-in gain or loss and the partner's share of net unrecognized section 704(c) gain or loss.
Part III holds the amounts. On the 2025 Schedule K-1 (Form 1065):
- Boxes 1 to 3 are ordinary business income and the two rental lines.
- Boxes 4a to 4c are guaranteed payments for services, for capital, and in total.
- Boxes 5 to 10 are portfolio and capital items: interest, ordinary and qualified dividends, dividend equivalents, royalties, short-term and long-term capital gain, collectibles gain, unrecaptured section 1250 gain and net section 1231 gain.
- Box 11 is other income, box 12 the section 179 deduction, box 13 other deductions.
- Box 14 is self-employment earnings, box 15 credits.
- Box 16 is a check box: "Schedule K-3 is attached if checked."
- Boxes 17 to 21 are AMT items, tax-exempt income and nondeductible expenses, distributions, other information, and foreign taxes paid or accrued.
- Boxes 22 and 23 are check boxes for more than one activity, for at-risk and passive activity purposes.
Guaranteed payments in boxes 4a to 4c are a partnership item. They are separate from the information returns a business sends to its contractors and landlords; which of those goes on which form is the subject of 1099-NEC vs 1099-MISC.
How do the 1120-S Schedule K-1 boxes differ?
The 1120-S Schedule K-1 boxes differ from the partnership version in three ways: the numbering shifts down, there are 19 boxes instead of 23, and some partnership items have no S corporation counterpart at all. Guaranteed payments and self-employment earnings do not appear. Part II tracks shares and shareholder loans instead of a capital account.
The 2025 Schedule K-1 (Form 1120-S) puts ordinary business income and the two rental lines in boxes 1 to 3, as the partnership form does. From box 4 the numbers part ways: box 4 is interest, boxes 5a and 5b are ordinary and qualified dividends, box 6 is royalties, and boxes 7 to 9 are the capital gain lines and net section 1231 gain.
Part II looks different. Item G is the current year allocation percentage, item H is the number of shares at the start and end of the year, and item I is loans from the shareholder. Part I adds item D, the corporation's total number of shares.
Two boxes have no direct partnership twin. Box 16 is "Items affecting shareholder basis", with codes for tax-exempt income, nondeductible expenses, distributions, repayment of loans from shareholders and foreign taxes. Box 17, "Other information", carries code V for Section 199A information. The Shareholder's Instructions for Schedule K-1 (Form 1120-S) (2025) describe each code.
For the rest of an S corporation's year-end paperwork, from the books to payroll filings, see the S corp checklist for year-end.
Key Schedule K-1 boxes side by side (2025 forms)
This table lines up where the same item sits on each 2025 version. "None" means the form has no box for that item.
| Item | 1065 K-1 | 1120-S K-1 | 1041 K-1 |
|---|---|---|---|
| Ordinary business income | Box 1 | Box 1 | Box 6 |
| Net rental real estate income | Box 2 | Box 2 | Box 7 |
| Other rental income | Box 3 | Box 3 | Box 8 |
| Guaranteed payments | Boxes 4a to 4c | None | None |
| Interest income | Box 5 | Box 4 | Box 1 |
| Ordinary dividends | Box 6a | Box 5a | Box 2a |
| Qualified dividends | Box 6b | Box 5b | Box 2b |
| Royalties | Box 7 | Box 6 | None (box 5 is other portfolio and nonbusiness income) |
| Net short-term capital gain | Box 8 | Box 7 | Box 3 |
| Net long-term capital gain | Box 9a | Box 8a | Box 4a |
| Collectibles (28%) gain | Box 9b | Box 8b | Box 4b |
| Unrecaptured section 1250 gain | Box 9c | Box 8c | Box 4c |
| Net section 1231 gain | Box 10 | Box 9 | None |
| Section 179 deduction | Box 12 | Box 11 | None |
| Self-employment earnings | Box 14 | None | None |
| Credits | Box 15 | Box 13 | Box 13 |
| Schedule K-3 check box | Box 16 | Box 14 | None |
| AMT items | Box 17 | Box 15 | Box 12 |
| Distributions | Box 19 | Box 16, code D | None |
| Other information | Box 20 | Box 17 | Box 14 |
| Final year deductions | None | None | Box 11 |
Schedule K-1 boxes on Form 1041 for trusts and estates
The Schedule K-1 boxes on Form 1041 report a beneficiary's share of an estate's or trust's income and deductions in 14 boxes. The order is different from the business versions: portfolio income comes first, business and rental income later, and two boxes exist only here, for the estate tax deduction and for deductions in the final year.
On the 2025 Schedule K-1 (Form 1041), box 1 is interest income, boxes 2a and 2b are ordinary and qualified dividends, box 3 is net short-term capital gain, and boxes 4a to 4c are net long-term capital gain, 28% rate gain and unrecaptured section 1250 gain. Box 5 is other portfolio and nonbusiness income. Boxes 6 to 8 are ordinary business income and the two rental lines. Box 9 is directly apportioned deductions and box 10 the estate tax deduction.
The final year gets special treatment. Item E is checked when "this is the final year of the estate or trust," in the words of the Instructions for Schedule K-1 (Form 1041) (2025). Box 11, final year deductions, then carries codes A to F: excess deductions on termination in two kinds, unused short-term and long-term capital loss carryovers, and unused net operating loss carryovers for regular tax and AMT.
The rest follows a familiar pattern. Box 12 is AMT adjustments, box 13 credits and credit recapture, and box 14 other information, with code I for Section 199A information and code H for a net investment income tax adjustment. The form also notes that a statement must be attached showing the beneficiary's share from each business, rental real estate and other rental activity.
Interest and dividends on a trust K-1 look like the amounts on a 1099-INT or 1099-DIV, but they reach the beneficiary through the trust. How those two forms differ when they arrive directly is covered in 1099-INT vs 1099-DIV.
Which Schedule K-1 box codes cause the most questions?
The Schedule K-1 box codes that cause the most questions are the lettered codes in the catch-all boxes: other income, other deductions and other information. A single box can hold several codes, each with its own meaning, and the ZZ code in each stands for "other", so the face page alone does not say what the amount is.
On the 2025 partnership K-1, these are the codes worth knowing by sight:
- Box 11, other income. Code A is other portfolio income, C is section 1256 contracts and straddles, E is cancellation of debt, S is non-portfolio capital gain or loss, and ZZ is other.
- Box 13, other deductions. Codes A to G are charitable contributions by limitation tier, H is investment interest expense, L is portfolio deductions, and ZZ is other.
- Box 19, distributions. Code A is cash and marketable securities, B is section 737 distributions, C is other property.
- Box 20, other information. Code A is investment income, B is investment expenses, Z is Section 199A information, and AA is section 704(c) information.
The partner's instructions describe where some of these go. For box 13, code H, they say "Include this amount on Form 4952, line 1." For box 20, codes A and B, they point to Form 4952, Part II, lines 4a and 5. For box 20, code Z, they say "The partnership will provide the information you need to figure your deduction," so the figures behind the code come from the partnership, not from the face page.
S corporation codes use different letters for similar ideas. Box 17, code V is Section 199A information on the 1120-S K-1, while the partnership uses box 20, code Z, and the trust K-1 uses box 14, code I. A preparer who memorizes one form's letters will misread the others. Always read the code against the instructions for that version and year.
Getting these codes into a spreadsheet, one row per box and code, is covered in a K-1 to Excel layout for clients with many K-1s. Schema CPA reads K-1s among the tax forms in a client's folder and exports what it reads to Excel or CSV; the list of document types it reads is on the homepage.
Schedule K-1 boxes that change basis, and why the K-1 alone is not enough
Several Schedule K-1 boxes change an owner's basis, but the K-1 alone cannot give the basis figure. Basis carries forward from every prior year, through contributions, income, losses and distributions the current K-1 does not show. The IRS instructions put the job of tracking it on the partner or shareholder, not on the form.
For partners, the 2025 instructions say: "It's the partner's responsibility to track and maintain the information necessary to figure their adjusted basis." They also warn that the item L capital account is not the same thing: the ending capital account may not equal the partner's adjusted tax basis, partly because tax-basis capital accounts leave out the partner's share of partnership liabilities. The instructions provide a worksheet for adjusting the basis of a partner's interest.
For S corporation shareholders, the 2025 instructions say: "You are responsible for keeping the information needed to figure the basis of your stock in the corporation." They direct shareholders to Form 7203, S Corporation Shareholder Stock and Debt Basis Limitations. Box 16 on the 1120-S K-1, items affecting shareholder basis, gives the current year's pieces: tax-exempt income, nondeductible expenses, distributions and loan repayments.
At-risk amounts need records too. For partners, the instructions say that generally only the amounts shown next to "Qualified nonrecourse financing" and "Recourse" in item K1 count toward the amount at risk. Those figures come from the current K-1, but the at-risk total, like basis, builds over years.
What this means for a firm's document request is practical. A K-1 client needs last year's basis records, prior K-1s for the same entity, and any record of contributions or loans during the year. When those records are missing, the K-1 is complete and the file still is not. Those records belong on the checklist next to the K-1 itself.