What Is California Form 100S?
California Form 100S is the S Corporation Franchise or Income Tax Return form filed with the California Franchise Tax Board. S corporations registered in California must file this return each year to report their total income, allowable deductions, and any tax due. The form covers all schedules necessary for S corporation tax reporting, including shareholder information and California-specific adjustments to federal income.
How Do You Complete California Form 100S?
You can fill out Form 100S directly on this page using the FormsPal online editor. Follow these steps to complete your filing:
- Click the Fill PDF Online button to open the form in the editor.
- Enter the S corporation name, California corporation number, and federal employer identification number (EIN) in the header section.
- Report total income for the tax year, including gross receipts, dividends, and other income sources.
- Complete the deductions section with allowable business expenses and depreciation amounts.
- Fill in each required schedule, including Schedule B (dividend income), Schedule C (tax credits), Schedule D (capital gains and losses), and Schedule K-1 for each shareholder.
- Calculate the total franchise or income tax due based on California tax rates.
- Review all entries for accuracy, then download, print, or save the completed PDF.
If you need more time to file, use California Form 100-WE to request an automatic extension of time to pay your balance due.
What Schedules Are Required With Form 100S?
The California Form 100S booklet includes the following schedules and supplementary forms:
- Schedule B - Reports dividend income deductions
- Schedule C - Details California tax credits available to S corporations
- Schedule D - Capital gains and losses from the tax year
- Schedule H - Shareholder and officer information
- Schedule QS - Qualified Subchapter S Subsidiary information
- Schedule K-1 - Each shareholder's share of income, deductions, and credits
- FTB 3539 - Payment voucher for automatic extension requests
- FTB 3805Q - Net operating loss computation and limitation worksheet
When Is the California Form 100S Due?
California S corporations must file Form 100S by the 15th day of the third month after the close of their tax year. For calendar year filers, this means the return is due on March 15. An automatic six-month extension is available by filing FTB Form 3539 and paying any estimated tax balance due by the original due date. Interest and penalties apply to any unpaid tax after the original filing deadline. Shareholders who file personal returns should also refer to the California Form 540-V for individual payment vouchers.
Where Can You Find the Latest California Form 100S Instructions?
The current year Form 100S instructions are published each year by the California Franchise Tax Board. The instructions cover all schedules, line-by-line guidance for reporting income and deductions, and updates to California tax law that differ from federal rules. You can access the official form and instructions through the FTB website or fill out the latest version of the form here on FormsPal using the online editor above.