U.S. · Tax forms
1120-S K-1 box 17 other information.
Code A investment income, code AC gross receipts, and why code W is not foreign taxes.
On an S corporation Schedule K-1, box 17 code A is investment income, reported on Form 4952, line 4a (investment expenses, code B, go on line 5). Code AC is gross receipts for section 448(c), used to figure the business interest expense you can deduct under section 163(j). Code W is not foreign taxes: codes W through Z are reserved for future use, and international tax items are handled in box 14 and Schedule K-3. Pick a code below to see what the IRS instructions say.
Look up a code
Result
Box 17 codes (2025 K-1)
| Box / code | Meaning | What it does and where it goes (per the IRS instructions) |
|---|---|---|
| 17 A | Investment income | Report this amount on Form 4952, line 4a. |
| 17 B | Investment expenses | Report this amount on Form 4952, line 5. |
| 17 C | Qualified rehabilitation expenditures (other than rental real estate) | The corporation will report your share of qualified rehabilitation expenditures and other information you need to complete Form 3468 for property not related to rental real estate activities in box 17 using code C. |
| 17 D | Basis of energy property | If the corporation provides an attached statement for code D, use the information on the statement to complete the applicable energy credit in Part VI of Form 3468. See the Instructions for Form 3468 for details. |
| 17 E and F | Recapture of low-income housing credit | The corporation will identify by code E your share of any recapture of a low-income housing credit from its investment in partnerships to which the provisions of section 42(j)(5) apply. All other recapture of low-income housing credits will be identified by code F. |
| 17 G | Recapture of investment credit | The corporation will provide any information you need to figure your recapture tax on Form 4255, Certain Credit Recapture, Excessive Payments, and Penalties. See the Form 3468 on which you took the original credit for other information you need to complete Form 4255. |
| 17 H | Recapture of other credits | On a statement attached to Schedule K-1, the corporation will report any information you need to figure the recapture of other credits including the new markets credit (Form 8874), Indian employment credit (Form 8845), credit for employer-provided childcare facilities and services (Form 8882), alternative fuel vehicle refueling property credit (Form 8911), and qualified plug-in electric drive motor vehicle credit (Form 8936). |
| 17 I | Look-back interest - completed long-term contracts | The corporation will report any information you need to figure the interest due or to be refunded under the look-back method of section 460(b)(2) on certain long-term contracts. Use Form 8697, Interest Computation Under the Look-Back Method for Completed Long-Term Contracts, to report any such interest. |
| 17 J | Look-back interest - income forecast method | The corporation will report any information you need to figure the interest due or to be refunded under the look-back method of section 167(g)(2) for certain property placed in service after September 13, 1995, and depreciated under the income forecast method. |
| 17 K | Dispositions of property with section 179 deductions | The corporation will report your share of gain or loss on the sale, exchange, or other disposition of property for which a section 179 expense deduction was passed through to shareholders with code K. |
| 17 L | Recapture of section 179 deduction | The corporation will report your share of any recapture of section 179 expense deduction if business use of any property for which the section 179 expense deduction was passed through to shareholders dropped to 50% or less before the end of the recapture period. If this occurs, the corporation must provide the following information. |
| 17 M | Section 453(l)(3) information | The corporation will report any information you need to figure the interest due under section 453(l)(3) with respect to the disposition of certain timeshares and residential lots on the installment method. Report the interest on Schedule 2 (Form 1040), line 14. See section 453(l)(3) for details on how to figure the interest. |
| 17 N | Section 453A(c) information | The corporation will report any information you need to figure the interest charge under section 453A(c) with respect to certain installment sales. See Pub. 537, Installment Sales. |
| 17 O | Section 1260(b) information | The corporation will report any information you need to figure the interest due under section 1260(b). If the corporation had gain from certain constructive ownership transactions, your tax liability must be increased by the interest charge on any deferral of gain recognition under section 1260(b). |
| 17 P | Interest allocable to production expenditures | The corporation will report any information you need relating to interest you are required to capitalize under section 263A for production expenditures. 263A-15 for details. |
| 17 Q | Capital construction fund (CCF) nonqualified withdrawals | The corporation will report your share of nonqualified withdrawals from a CCF. These withdrawals are taxed separately from your other gross income at the highest marginal ordinary income or capital gains tax rate. |
| 17 R | Depletion information - oil and gas | This is your share of gross income from the property, share of production for the tax year, and other information needed to figure your depletion deduction for oil and gas wells. The corporation should also allocate to you a proportionate share of the adjusted basis of each corporate oil or gas property. |
| 17 S and T | Reserved for future use | Reserved for future use in the IRS instructions. |
| 17 U | Net investment income | The corporation may use code U to report information you may need to determine your net investment income tax under section 1411, including information regarding income from controlled foreign corporations (CFCs) and passive foreign investment companies (PFICs), the stock of which is owned by the corporation. |
| 17 V | Section 199A information | Generally, you may be allowed a deduction of up to 20% of your net qualified business income (QBI) plus 20% of your qualified REIT dividends, also known as section 199A dividends, and qualified publicly traded partnership (PTP) income from your S corporation. |
| 17 W through Z | Reserved for future use | Reserved for future use in the IRS instructions. |
| 17 AA | Excess taxable income | If the S corporation is required to file Form 8990, Limitation on Business Interest Expense Under Section 163(j), it may determine it has excess taxable income. Report this amount of excess taxable income in column (c) of Form 8990, Schedule B, line 45, if you are required to file Form 8990. See the Instructions for Form 8990 for details. |
| 17 AB | Excess business interest income | If the S corporation is required to file Form 8990, it may determine it has excess business interest income. Report this amount of excess business interest income in column (d) of Form 8990, Schedule B, line 45, if you are required to file Form 8990. See the Instructions for Form 8990 for details. |
| 17 AC | Gross receipts for section 448(c) | Use the gross receipts amount to figure the business interest expense you can deduct, if applicable. See section 163(j) and the Instructions for Form 8990 for details. |
| 17 AD through AI | Reserved for future use | Reserved for future use in the IRS instructions. |
| 17 AJ | Excess business loss limitation | If the corporation has deductions attributable to a business activity, it'll provide a statement gain, showing the aggregate gross income or gain and the aggregate deductions from the business activity of all the corporation's trades or businesses. |
| 17 AK through AM | Reserved for future use | Reserved for future use in the IRS instructions. |
| 17 AN | Farming and fishing income | If you are an individual shareholder, report this income, as an item of information, on Schedule E (Form 1040), Part V, line 42. Don't report this income elsewhere on Form 1040 or 1040-SR. |
| 17 AO | Reserved for future use | Reserved for future use in the IRS instructions. |
| 17 AP | Inversion gain | The corporation will provide a statement showing the amounts of each type of income or gain that is included in inversion gain. The corporation has included inversion gain in income elsewhere on Schedule K-1. |
| 17 AQ and AR | Reserved for future use | Reserved for future use in the IRS instructions. |
| 17 AS | Qualifying advanced coal project property and qualifying gasification project property | For qualified investment in qualifying advanced coal project property, use the amounts the corporation provides you to figure the amounts to report on Form 3468, Part II, Section A, lines 1a, 2a, and 3a. |
| 17 AT | Qualifying advanced energy project property | Use the amounts the corporation provides you to figure the amounts to report on Form 3468, Part III, line 1a. |
| 17 AU | Advanced manufacturing investment property | Use the amounts the corporation provides you to figure the amount to report on Form 3468, Part IV, line 1b. |
| 17 AV | Clean electricity investment | Use the amounts the corporation provides you to figure the amount to report on Form 3468, Part V, line 1a. |
| 17 AW | Reportable transactions | Any information you need to complete a disclosure statement for reportable transactions in which the corporation participates. |
| 17 AX through AZ | Reserved for future use | Reserved for future use in the IRS instructions. |
| 17 BA | Domestic research or experimental expenditures | P.L. 119-21 added section 174A, which pertains to domestic research and experimental expenditures. Section 174A(a) allows a deduction for domestic research and experimental expenditures paid or incurred during the tax year for tax years beginning after 2024. |
| 17 BB through BD | Reserved for future use | Reserved for future use in the IRS instructions. |
| 17 ZZ | Other | Any other information you may need to file your return not shown elsewhere on Schedule K-1. Interest on loans secured by rural or agricultural real property. P.L. 119-21 enacted new section 139L that allows a qualified lender to exclude 25% of the interest income on qualified loans secured by rural or agricultural real property. |
Code A and code B: investment interest
If the corporation has investment income or other investment expense, it reports your share in box 17 with codes A and B. Code A goes on Form 4952, line 4a, and code B on line 5. The instructions tell you to include investment income and expenses from other sources to figure how much of your total investment interest is deductible.
Code AC is the section 163(j) number, not a deduction
Code AC reports gross receipts for section 448(c). The instructions say to use it to figure the business interest expense you can deduct, if applicable, and send you to section 163(j) and the Instructions for Form 8990. The same section covers code AA (excess taxable income) and code AB (excess business interest income), which go in columns (c) and (d) of Form 8990, Schedule B, line 45 if you must file Form 8990. Codes AA to AC are information items: they are not an amount you deduct or add to income.
Code W is reserved
Searches for "box 17 code W total foreign taxes" lead nowhere on this form. The instructions list codes W through Z as reserved for future use. International tax items on an S corporation K-1 are handled in box 14 (International Transactions), and the instructions send you to Schedule K-3 (Form 1120-S) for them. If you see a letter that is marked reserved, ask the corporation what it meant.
Codes you may see often
Code V is the section 199A (QBI) information, with its own page. Code U is net investment income information for the section 1411 tax, and you follow the Instructions for Form 8960. Code AN is farming and fishing income, shown on Schedule E (Form 1040), Part V, line 42 for individuals. Code K reports dispositions of property with section 179 deductions, and the corporation provides a list of details to complete Form 4797. Code BA is domestic research or experimental expenditures under section 174A.
Limits of this page
Where the instructions give a long list of items, the table shows only the first part of the entry. Read the full entry for any code you have. The matching credit codes are on the box 13 page and basis items are on the box 16 page.
Sources
- Instructions for Schedule K-1 (Form 1120-S) (2025): Box 17, Other Information, and the List of Codes, codes A to ZZ; Box 14 (International Transactions) heading. Read November 2, 2026.
IRS instruction pages last reviewed April 30, 2026. Form and line references are those printed in the 2025 forms and instructions and can change.
Frequently asked questions
What is box 17 code A on an S corporation K-1?
Investment income. Report it on Form 4952, line 4a.
What is box 17 code AC on a Schedule K-1 (Form 1120-S)?
Gross receipts for section 448(c). You use it to figure the business interest expense you can deduct, if applicable, under section 163(j) and the Instructions for Form 8990.
Is box 17 code W total foreign taxes?
No. The instructions say codes W through Z are reserved for future use. International tax items are handled in box 14, International Transactions, and Schedule K-3.
Where does box 17 code B go?
Investment expenses go on Form 4952, line 5.
What does a reserved code mean on a K-1?
It means the IRS has set the code aside for later use and does not use it on the 2025 form. If one appears on your K-1, ask the corporation what it is reporting.
Not tax advice
This page summarizes IRS instructions, mostly written for the people who prepare the form, and is not tax, legal or financial advice. The estate, trust or corporation that issued the K-1, a CPA or an enrolled agent can confirm what a box or code means for your return. Everything runs in your browser; nothing you enter is sent anywhere.