100S: California S Corporation Franchise or Income Tax Return (2024)
California · FTB · Used for tax years 2024
Form 100S is the 2024 California S Corporation Franchise or Income Tax Return. It reports income, state adjustments, deductions, credits, taxes, and payments to determine the corporation’s refund or amount due.
What you'll need
Have the corporation’s identifying information ready, including its California corporation number, FEIN, California Secretary of State file number, and address.
Depending on the items reported, the form calls for these documents:
- Federal Form 1120-S, page 1, and supporting schedules: Attach these if Schedule F of Form 100S was not completed.
- Schedule D (100S): For the capital gains and tax entries that require it.
- Schedule B (100S): For depreciation and amortization adjustments and the Schedule K Section 179 expense deduction.
- Schedule H (100S): For the dividends received deduction and water’s-edge dividend deduction.
- Schedule C (100S): For the total credits on line 25.
- Schedule R: Use this if apportioning or allocating income.
- Forms 592-B and/or 593: For the 2024 withholding entry.
- Federal Form 8886: Complete and attach one for each reportable or listed transaction included in the return.
- Federal Form 8825: Attach for net rental real estate income or loss on Schedule K.
Other entries call for supporting schedules, including certain income, deductions, assets, liabilities, and inventory costs. Attach those where the form requests them.
Common mistakes
- Leaving required fields blank: Schedule Q says not to leave the principal business activity code or the maximum number of shareholders during the year blank.
- Treating line 37 as a total: Line 37 is for use tax. The form specifically says it is not a total line.
- Missing the property ownership reporting requirement: A “Yes” answer to the Schedule Q, Part B questions requires filing a BOE-100-B statement. The form warns that penalties may apply.
- Using the wrong figures for inventory costs: Schedule V includes an important reminder to use California figures and federal procedures.
Questions people ask
Can I use federal Form 1120-S for the ordinary business income entry?
Yes. Line 1 accepts ordinary trade or business income or loss from Schedule F, line 22, or federal Form 1120-S, line 22. If Schedule F was not completed, attach federal Form 1120-S, page 1, and supporting schedules.
Can an overpayment go toward next year’s estimated tax?
Yes. On the 2024 form, line 42 lets you enter the amount of the line 41 overpayment to credit toward 2025 estimated tax. Line 43 shows the refund after subtracting line 42 from line 41.
Does the form allow direct deposit of a refund?
Yes. The form provides fields for a routing number, checking or savings account type, and account number. It directs you to the instructions for direct deposit details.
Must every corporation complete Schedules L and M-1?
Not necessarily. The form says the corporation may not be required to complete these schedules and refers to their instructions for reporting requirements. Those instructions are not included in the supplied text.
What if the corporation changed how it determined inventory quantities, costs, or values?
Schedule V asks whether there was a change between opening and closing inventory. If you answer “Yes,” attach an explanation.