This Schedule B-1 Form 1120-S guide explains the IRS Information on Certain Shareholders of an S Corporation. Schedule B-1 for Form 1120-S supplies additional shareholder information for the situations covered by the schedule. The shareholder type and identifying details must agree with the corporation records. It is distinct from the partnership ownership schedule with a similar label.
Reviewed October 31, 2026. This is an independent guide. The version and availability information below identifies the IRS documents used for this page.
What Schedule B-1 Form 1120-S does and who prepares it
An S corporation reports the specified information on certain shareholders required by its instructions.
For the connected reporting route, see Form 1120-S. Keep the role of that document separate from the task explained on this page.
| Official form | Form 1120-S (Schedule B-1) |
|---|---|
| IRS title | Information on Certain Shareholders of an S Corporation |
| Guide period | the applicable reporting period |
| Target version | Dec 2020 |
| Availability | Current IRS catalog PDF |
| Last checked | October 31, 2026 |
Get the Schedule B-1 Form 1120-S PDF and check its status
Use the IRS source to confirm the document before completing a real filing. The download link is a reference to the official file; it is not a statement that every copy inside the PDF may be printed and submitted. Follow any instructions about electronic filing, scannable copies, recipient copies or attachments.
Which version of Schedule B-1 Form 1120-S should you use?
This form follows a revision or continuing-use format rather than a new title for every calendar year. Check the revision printed on the document and the period requested inside it. A revision date, transaction date and tax year are different pieces of information. The current document should be read with the instructions that apply to the actual transaction or return.
Records to gather for Schedule B-1 Form 1120-S
- Shareholder register.
- Shareholder classification records.
- Identifying information.
- Relevant ownership documents.
- S corporation return.
Keep a working reconciliation with these records. It should show the source of each reported item, any correction made before filing and the reason a different amount appears on a connected form. This is especially useful when a statement is corrected or a prior-year balance continues into the current calculation.
How to work through Schedule B-1 Form 1120-S
- Confirm applicability. Start with the purpose, filer category and version of the form. Complete any eligibility or applicability question before spending time on the numerical calculation.
- Prepare the source workpapers. Gather the records listed below and reconcile their totals. Keep prior-year balances, current-year transactions and estimated payments separate where they serve different purposes.
- Complete dependent calculations first. When a line refers to another form, schedule or worksheet, finish that supporting calculation first. Preserve any classification, limitation and carryforward information.
- Follow the line sequence. Use the actual line labels and arithmetic in the applicable form. A line number from an older version may refer to something different after a revision.
- Reconcile the filing package. Check names, identifying numbers, tax periods, totals and required attachments. Then use the filing method, signature process and deadline that apply to this filer and form.
Form-specific IRS instructions and reporting details
The following points retain the operative wording of the IRS documents linked above. Read each point with its stated conditions and the applicable form version. References to another form or section describe a connected requirement; they do not mean that every reader must file every referenced document.
In general, section 465 limits the amount of deductible net losses shareholders can claim from certain activities. The at-risk limitations don’t apply to the corporation, but instead apply to each shareholder’s share of net losses attributable to each activity. Because the treatment of each shareholder’s share of corporate net losses depends on the nature of the activity that generated it, the corporation must report the items of income, loss, and deduction separately for each activity. See Pub. 925, Passive Activity and At-Risk Rules, for additional information.
Additional reporting conditions
A trade or business activity is an activity (other than a rental activity or an activity treated as incidental to an activity of holding property for investment) that: 1. Involves the conduct of a trade or business (within the meaning of section 162), 2. Is conducted in anticipation of starting a trade or business, or 3. Involves the conduct of research or experimental activities, including software development, subject to either section 174 (foreign research) or section 174A (domestic research).
If the shareholder doesn’t materially participate in the activity, a trade or business activity of the corporation is a passive activity for the shareholder. Each shareholder must determine if they materially participated in an activity. As a result, while the corporation’s ordinary business income (loss) is reported on Form 1120-S, page 1, the specific income and deductions from each separate trade or business activity must be reported on attachments to Form 1120-S.
Similarly, while each shareholder’s allocable share of the corporation’s ordinary business income (loss) is reported in box 1 of Schedule K-1, each shareholder’s allocable share of the income and deductions from each trade or business activity must be reported on statements attached to each Schedule K-1. See Passive Activity Reporting Requirements, later, for more information.
Calculations and supporting information
Certain self-charged interest income and deductions may be treated as passive activity gross income and passive activity deductions if the loan proceeds are used in a passive activity. Generally, self-charged interest income and deductions result from loans between the corporation and its shareholders. Self-charged interest also occurs in loans between the corporation and another S corporation or partnership if each owner in the borrowing entity has the same proportional ownership interest in the lending entity.
The self-charged interest rules don’t apply to a shareholder’s interest in an S corporation if the S corporation makes an election under Regulations section 1.469-7(g) to avoid the application of these rules. To make the election, the S corporation must attach to its original or amended Form 1120-S a statement that includes the name, address, EIN of the S corporation, and a declaration that the election is being made under Regulations section 1.469-7(g). The election will apply to the tax year for which it was made and all subsequent tax years.
Once made, the election can only be revoked with the consent of the IRS. For more details on the self-charged interest rules, see Regulations section 1.469-7.
Exceptions and related reporting
For purposes of determining the corporation’s constructive ownership of other entities, the constructive ownership rules of section 267(c) (excluding section 267(c)(3)) apply to ownership of interests in partnerships and trusts as well as corporate stock. Generally, if an entity (a corporation, partnership, or trust) is owned, directly or indirectly, by or for another entity (corporation, partnership, estate, or trust), the owned entity is considered to be owned proportionately by or for the owners (shareholders, partners, or beneficiaries) of the owning entity.
Schedule K. Schedule K is a summary schedule of all shareholders’ shares of the corporation’s income, deductions, credits, etc. All corporations must complete Schedule K. Schedule K-1. Schedule K-1 shows each shareholder’s separate share. Attach a copy of each Schedule K-1 to the Form 1120-S filed with the IRS. Keep a copy for the corporation’s records and give each shareholder a copy.
Further form details
Line 1. Ordinary Business Income (Loss) Enter the amount from Form 1120-S, page 1, line 22. Enter the income (loss) without reference to the shareholder’s: • Basis in the stock of the corporation and in any indebtedness of the corporation to the shareholders (section 1366(d)), • At-risk limitations, and • Passive activity limitations. These limitations, if applicable, are determined at the shareholder level. Line 1 shouldn’t include rental activity income (loss) or portfolio income (loss). Schedule K-1. Enter each shareholder’s pro rata share of ordinary business income (loss) in box 1 of Schedule K-1.
Identify on statements attached to Schedule K-1 any additional information the shareholder needs to correctly apply the passive activity limitations. For example, if the corporation has more than one trade or business activity, identify the amount from each activity. See Passive Activity Reporting Requirements, earlier.
Specific instructions for Statement C—QBI Pass-Through Entity Reporting—Patrons of Specified Agricultural and Horticultural Cooperatives. QBI items and W-2 wages allocable to qualified payments. If the S corporation is a patron of a specified agricultural or horticultural cooperative, the S corporation must provide the pro rata share of QBI items and W-2 wages allocable to qualified payments from each trade or business to each of its shareholders on Statement C, or a substantially similar statement, and attach it to each Schedule K-1 so each shareholder can figure their patron reduction under section 199A(b)(7).
Further form details
Use Schedule B-1 (Form 1120-S) to provide the information applicable to any shareholder in the S corporation that was a disregarded entity, a trust, an estate, or a nominee or similar person at any time during the tax year. If the shareholder was a disregarded entity, provide the information even if the name, address, and social security number (SSN) or employer identification number (EIN) (if any) of the owner of the disregarded entity was entered on Schedule K-1 (Form 1120-S), Shareholder’s Share of Income, Deductions, Credits, etc.
If the shareholder was a nominee, guardian, custodian, or agent, provide the information even if the name, address, and SSN or EIN (if any) of the person for whom the stock was held was entered on Schedule K-1 (Form 1120-S).
Who Must File Schedule B-1 (Form 1120-S) must be filed by all S corporations that answer “Yes” to Form 1120-S, Schedule B, question 3. Attach Schedule B-1 to Form 1120-S.
A practical example
An S corporation reviews its shareholder types before filing. The preparer identifies any shareholders covered by the additional information requirement and checks the schedule against the corporate records.
This example illustrates the order of the review. It does not assume an unverified deduction, exemption, treaty rate or final tax amount. The applicable form instructions and the actual records determine the result.
Common mistakes to avoid with Schedule B-1 Form 1120-S
- Use the S corporation schedule rather than the partnership schedule.
- Confirm the shareholder categories that trigger reporting.
- Reconcile the disclosures with the shareholder statements.
Questions about Schedule B-1 Form 1120-S
Does receiving or downloading this form mean I must file it?
An S corporation reports the specified information on certain shareholders required by its instructions. The form purpose and the applicable filing or furnishing conditions determine the action. Downloading a blank PDF does not itself create a filing obligation or establish eligibility for a tax benefit.
Is the revision date always the same as the tax year?
No. Some forms show a tax year, while continuing-use forms show a revision date and ask separately for the reporting period. Check the actual document and instructions. Do not relabel a payment or transaction solely because it was reported in a later calendar year.
What should I do if the underlying information is wrong?
Use the S corporation schedule rather than the partnership schedule. Keep the original record and the correction trail. The issuer correction process, an amended return and an updated certificate can be different procedures. Choose the process that matches the document and the actual error.
Which records should I keep with the completed form?
Retain the source documents, applicable worksheets, submitted version and filing or furnishing confirmations. For this form, the working file should include shareholder register, shareholder classification records, identifying information. Keep continuing balances and prior-year support for as long as they remain relevant under the applicable recordkeeping rules.
Related forms and next steps
Use these guides when the connected issue applies to your records. Each page has its own purpose, reporting year and availability status.