U.S. · Tax forms
Form 1120 Schedule J line 18, withholding.
Schedule J, line 18 is not page 1, line 18. See what the IRS says to put there.
Schedule J, line 18 (“Withholding”) takes federal income tax withheld from payments the corporation received, for example because it did not give the payer its correct EIN or was subject to backup withholding. Tax withheld under chapter 3 or 4 (Form 1042-S, 8805 or 8288-A) is handled on the line 20 credits instead.
Look up a withholding case
Result
Where withholding goes, 2025 instructions
| Case | Meaning | What the IRS says |
|---|---|---|
| Backup withholding | Schedule J, line 18 | Federal income tax withheld because the corporation failed to give the payer its correct EIN or was otherwise subject to backup withholding |
| Other income tax withheld on payments received | Schedule J, line 18 | The instructions say to include the amount withheld in the total for line 18 |
| Chapter 3 or 4 withholding | Schedule J, line 20z | Tax withheld under chapter 3 or 4 shown on Form 1042-S, Form 8805 or Form 8288-A; attach the form to claim the credit |
| Credit under line 20c | Printed on the form | The 2025 form also has line 20c, “Credit for tax withheld under chapter 3 or 4 from Form 1042-S, Form 8805, or Form 8288” |
| Total payments | Schedule J, line 19 | Combine lines 13 through 18 |
| Page 1 line 18 | Interest | A deduction line on page 1, not withholding |
Line 18 versus the chapter 3 or 4 credits
The 2025 instructions for payments say that if the corporation had tax withheld under chapter 3 or 4 of the Internal Revenue Code and received a Form 1042-S, Form 8805 or Form 8288-A showing the amount, it should attach the form and report the tax withheld on Schedule J, line 20z. The instructions for line 20c separately describe a credit for tax withheld under chapter 3 or 4. Follow the instructions for the form that was issued.
The page 1 trap
Page 1, line 18 is “Interest (see instructions),” a deduction. The withholding line is on Schedule J.
Where it flows
Line 18 is part of Schedule J line 19 total payments, and line 23 carries the full total of payments and credits to page 1, line 33.
Worked example
Copper Mill Imports, Inc. (made up) had $1,200 of federal income tax withheld from payments received because it had not given the payer its correct EIN. Schedule J, line 18 shows $1,200, which is added with other payments on line 19. Names and figures are made up.
More line pages in this set
Related lines: Form 1120 Line 11, Form 1120 Line 26, Form 1120 Line 28, Form 1120 Line 29a, Form 1120 Line 30, Form 1120 Schedule J Line 12, Form 1120 Schedule J Line 17.
Sources
- Instructions for Form 1120 (2025): the line-by-line instructions on this page. Page last reviewed or updated April 30, 2026. Read November 2, 2026.
- Form 1120 (2025), U.S. Corporation Income Tax Return: the printed line wording and arithmetic on the form (Form 1120 (2025), created 9/26/25). Read November 2, 2026.
Tax year 2025 forms and instructions: Form 1120 (2025) and its 2025 instructions. Line numbers and labels were read from the IRS PDF and instructions on the date read and can change between tax years, so check them against the form for your year. Names in worked examples are made up.
Frequently asked questions
What is Form 1120 line 18 on Schedule J?
Withholding: federal income tax withheld from payments the corporation received, such as backup withholding.
Is page 1 line 18 withholding?
No. Page 1, line 18 is Interest, a deduction.
Where does chapter 3 or 4 withholding go?
The instructions say to attach Form 1042-S, Form 8805 or Form 8288-A and report the tax withheld on Schedule J, line 20z.
What causes backup withholding?
The instructions give as an example that the corporation failed to give the payer its correct EIN.
How does line 18 total with other payments?
Schedule J, line 19 combines lines 13 through 18.
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. A CPA or an enrolled agent can confirm what a line means for your return. Everything runs in your browser; nothing you enter is sent anywhere.