Updated October 18, 2026. Quick answer: Schedule K lines 15 to 21 are the partnership’s totals for credits, international filing boxes, alternative minimum tax items, and the Other Information items such as tax-exempt income, distributions, investment income and foreign taxes. Each total comes from the partnership’s own records and the credit or AMT forms the instructions name, and each is then split among partners on Schedule K-1.
What these lines are
These lines sit in the second half of Schedule K, on page 5 of the Form 1065 return. The form groups them under four headings: Credits (lines 15a to 15f), International (lines 16a and 16b), Alternative Minimum Tax (AMT) Items (lines 17a to 17f) and Other Information (lines 18a to 21). The earlier lines are covered on the pages for Schedule K lines 1 to 4, Schedule K lines 5 to 11 and Schedule K lines 12 to 14.
Credits: lines 15a to 15f
The form’s captions are the starting point. Line 15a reads “Low-income housing credit (section 42(j)(5))”, line 15b reads “Low-income housing credit (other)”, and line 15c reads “Qualified rehabilitation expenditures (rental real estate) (attach Form 3468, if applicable)”.
| Line | What the instructions say |
|---|---|
| 15a | “Enter on line 15a the total low-income housing credit for property which a partnership is to be treated under section 42(j)(5) as the taxpayer to which the low-income housing credit was allowed.” |
| 15b | “Enter on line 15b any low-income housing credit not reported on line 15a.” |
| 15c | “Enter on line 15c the total qualified rehabilitation expenditures related to rental real estate activities of the partnership.” |
| 15d | “Enter on line 15d any other credit (other than credits reported on lines 15a through 15c) related to rental real estate activities.” |
| 15e | “Enter on line 15e any other credit (other than credits reported on lines 15a through 15d) related to rental activities.” |
| 15f | “Enter on line 15f any other credit, except credits or expenditures shown or listed on lines 15a through 15e.” |
For line 15f the instructions add: “On the dotted line to the left of the entry space for line 15f, identify the type of credit.” “If there’s more than one type of credit or if there are any credits subject to recapture, attach a statement to Form 1065”. For lines 15d and 15e the same idea applies: “These credits may include any type of credit listed in the instructions for line 15f.”
International: lines 16a and 16b
Line 16a is a check box, not an amount. The form’s caption begins “Attach Schedule K-2 (Form 1065), Partners’ Distributive Share Items” and line 16b reads “Check this box if you qualified for an exception to filing Schedule K-2”. The instructions say “If the partnership had items of international tax relevance, see the Partnership Instructions for Schedules K-2 and K-3 (Form 1065) to determine if you need to attach Schedules K-2 and K-3.” For 16b they say “Check this box if an exception applies.”
AMT items: lines 17a to 17f
The instructions open this group with “Lines 17a through 17f must be completed for all partners.” “Enter items of income and deductions that are adjustments or tax preference items for the AMT.”
| Line | Form caption | What the instructions say |
|---|---|---|
| 17a | “Post-1986 depreciation adjustment” | “Figure the adjustment by subtracting the AMT deduction for depreciation from the regular tax deduction and enter the result on line 17a.” |
| 17b | “Adjusted gain or loss” | “Enter on this line the difference between the regular tax gain (loss) and the AMT gain (loss).” |
| 17c | “Depletion (other than oil and gas)” | “Enter the difference between the regular tax and AMT deduction.” |
| 17d | “Oil, gas, and geothermal properties” gross income | “Enter the total amount of gross income (within the meaning of section 613(a)) from all oil, gas, and geothermal properties received or accrued during the tax year and included on page 1 of Form 1065.” |
| 17e | “Oil, gas, and geothermal properties” deductions | “Enter any deductions allowed for the AMT that are allocable to oil, gas, and geothermal properties.” |
| 17f | “Other AMT items (attach statement)” | “Attach a statement to Form 1065 and Schedule K-1 that shows other items not shown on lines 17a through 17e that are adjustments or tax preference items” |
For lines 17d and 17e the instructions explain the scope: “Generally, the amounts to be entered on lines 17d and 17e are only the income and deductions for oil, gas, and geothermal properties that are used to figure the partnership’s ordinary income (loss) (Form 1065, line 23).” For the amounts themselves they send you to “Form 6251, Alternative Minimum Tax” and the Schedule I (Form 1041) instructions. For the depreciation side, the partnership’s Form 4562 work is on the Form 4562 page.
Other information: lines 18a to 18c
Line 18a reads “Tax-exempt interest income”. The instruction is “Enter on line 18a tax-exempt interest income, including any exempt-interest dividends received from a mutual fund or other RIC.” Line 18b: “Enter on line 18b all income of the partnership exempt from tax other than tax-exempt interest.” Line 18c: “Enter on line 18c nondeductible expenses paid or incurred by the partnership.” “Don’t include separately stated deductions shown elsewhere on Schedules K and K-1, capital expenditures, or items the deduction for which is deferred to a later tax year.”
Other information: lines 19a to 21
Line 19a: “Enter the distributions of cash (including deemed distributions of money under section 752(b)) and marketable securities made to the partners by combining amounts reported using codes A, D, and F.” Line 19b: “Enter the distributions of property to partners not reported on line 19a by combining amounts reported using codes B, C, and G.” The distributions rows tie to the partners’ side on the Schedule K-1 box 19 page.
Line 20a: “Enter on line 20a the investment income included on Schedule K, lines 5, 6a, 7, and 11.” “Don’t include other portfolio gains or losses on this line.” Line 20b: “Enter investment expenses on line 20b.” “Investment expenses are deductible expenses (other than interest) directly connected with the production of investment income.” Line 20c is an attachment line: “Report the following information on a statement attached to Form 1065.” Investment items for the partner are discussed at Form 4952.
Line 21: “Enter in U.S. dollars the total creditable foreign taxes (described in section 901 or 903) that were paid or accrued by the partnership”. The instructions limit what the line does: “The information on line 21 is solely for purposes of computing basis.” “A partnership must complete Schedules K-2 and K-3 to provide the information necessary for the partner to claim a foreign tax credit.”
Where the number comes from
Credit amounts come from the credit forms the instructions name for the line (for example, Form 3468 for rehabilitation expenditures, as printed in the line 15c caption). AMT amounts come from refiguring the regular tax item under the AMT rules the instructions describe. Lines 18 to 21 come from the partnership’s books and records for the year, and the instructions for each line say which items belong there.
Where it goes next
Each total is passed to the partners. For credits, “Report in box 15 of Schedule K-1 each partner’s distributive share of the low-income housing credit reported on line 15a of Schedule K.” For AMT: “Report each partner’s distributive share of amounts reported on lines 17a through 17f (concerning AMT) in box 17 of Schedule K-1 using codes A through F, respectively.” For lines 18a to 18c: “Report in box 18 of Schedule K-1 each partner’s distributive share of amounts reported on lines 18a, 18b, and 18c of Schedule K”. For lines 20a and 20b: “Report each partner’s distributive share of amounts reported on lines 20a and 20b (investment income and expenses) in box 20 of Schedule K-1 using codes A and B, respectively.”
Line 21 also feeds the analysis on page 6. The Analysis of Net Income (Loss) per Return line 1 reads “Combine Schedule K, lines 1 through 11.” “From the result, subtract the sum of Schedule K, lines 12 through 13e, and 21”. That calculation is on the Schedule M-1 and the analysis of net income page.
Edition and line numbers
This page reads the 2025 Form 1065 and its 2025 instructions, the current files irs.gov served on 2026-10-18. They are the files for the tax year 2025 return, filed in 2026. Form 1065 carries no “Attach to” caption, so the form’s own title line is the identifier: “U.S. Return of Partnership Income”, with the header “For calendar year 2025, or tax year beginning”. Check the tax year printed on the form you are filling in and use the line numbers on that year’s form, because a different year’s form can number or word its lines differently.
Common mistakes
- Using line 15f for a credit that has its own line. The instructions say “Enter on line 15f any other credit, except credits or expenditures shown or listed on lines 15a through 15e.”
- Leaving off the credit type or the statement. The instructions say “On the dotted line to the left of the entry space for line 15f, identify the type of credit.”
- Treating line 21 as the partner’s foreign tax credit figure. The instructions say “The information on line 21 is solely for purposes of computing basis.”
Related: Form 1065, Form 4562, Form 4952, and Schedule K-1 box 19.
Sources
- Instructions for Form 1065, U.S. Return of Partnership Income (2025): https://www.irs.gov/pub/irs-pdf/i1065.pdf
- Form 1065, U.S. Return of Partnership Income (2025): https://www.irs.gov/pub/irs-pdf/f1065.pdf
Read from the IRS documents linked above on October 18, 2026. General information, not tax advice. Your own facts decide the outcome, and a preparer, the account provider or the IRS is the right place to confirm anything consequential.