California Payroll Tax Guide for Small Business Owners

If you employ anyone in California -- including yourself as an S-Corp shareholder-employee -- you are responsible for understanding and complying with the state's payroll tax system. California has four distinct payroll taxes, each with its own rates, wage bases, and rules. Getting these wrong can result in penalties, interest, and back-assessments from the Employment Development Department (EDD).

This guide covers everything Bay Area small business owners need to know about California payroll taxes, from registration through quarterly filing. Whether you just made an S-Corp election or you are hiring your first employee, this is your roadmap to staying compliant.

The Four California Payroll Taxes

California imposes four separate employment taxes. Two are paid by the employer, one is paid by the employee, and one involves withholding from the employee's wages.

1. State Disability Insurance (SDI)

Paid by: Employee (withheld from wages)
Rate: 1.1% of taxable wages (2025 rate)
Wage base: $167,000 (2025)

SDI provides short-term disability benefits and funds the Paid Family Leave (PFL) program. As an employer, you withhold SDI from each employee's paycheck and remit it to the EDD. S-Corp shareholder-employees are generally subject to SDI.

2. State Unemployment Insurance (SUI)

Paid by: Employer
Rate: 1.5% to 6.2% (new employers typically start at 3.4%)
Wage base: $7,000 per employee per year

SUI funds unemployment benefits for workers who lose their jobs through no fault of their own. Your rate is determined by your experience rating; new employers start at 3.4%. Because the wage base is only $7,000, the maximum SUI cost per employee is modest -- between $105 and $434 per year.

3. Employment Training Tax (ETT)

Paid by: Employer
Rate: 0.1%
Wage base: $7,000 per employee per year

ETT funds employee training programs administered through the EDD. The maximum ETT per employee is $7.00 per year. While the amount is trivial, it must be tracked, reported, and remitted with your other payroll tax deposits. Failing to include it can trigger notices and compliance issues.

4. Personal Income Tax (PIT) Withholding

Paid by: Employee (withheld from wages)
Rate: Variable based on employee's W-4/DE 4 and California tax brackets
Wage base: No limit

As an employer, you are required to withhold California personal income tax from each employee's wages based on the information they provide on their DE 4 (Employee's Withholding Allowance Certificate). California's progressive tax rates range from 1% to 13.3%, so accurate withholding is essential to avoid underwithholding penalties for your employees.

Summary of Rates and Wage Bases

Rates shown are for the 2025 tax year. Check the EDD website for current-year updates.

Registering with the EDD

Before you can pay employees or yourself as an S-Corp shareholder-employee, you must register with the California EDD. Here is the process:

1. Obtain your federal EIN from the IRS (Form SS-4 or online at IRS.gov) if you do not already have one
2. Register online through the EDD's e-Services for Business portal at edd.ca.gov
3. Receive your EDD account number -- this is an 8-digit number used for all California payroll tax filings
4. Receive your SUI rate notice -- the EDD will assign your initial unemployment insurance rate

You must register within 15 days of paying $100 or more in wages in a calendar quarter. For S-Corp owners paying themselves, registration should happen before your first payroll run.

Filing Deadlines and Required Forms

Quarterly Filing

Every quarter, you must file two forms with the EDD:

• DE 9 (Quarterly Contribution Return and Report of Wages) -- reports total wages, tax amounts due, and payment. This is the return that reconciles your quarterly payroll tax liability.
• DE 9C (Quarterly Contribution Return and Report of Wages -- Continuation) -- reports individual employee wage detail, including each employee's Social Security number, name, and quarterly wages.

Both forms are due by the last day of the month following the end of each quarter:

Deposit Schedules and New Hire Reporting

Payroll tax deposits follow a monthly or semi-weekly schedule depending on your liability amount. Most small businesses with just the owner on payroll fall into the monthly or quarterly deposit category. California also requires employers to report all new hires within 20 days of their start date using the DE 34 form, including S-Corp shareholder-employees when they first go on payroll.

Common Payroll Tax Mistakes

In our business tax practice, we regularly see these payroll tax errors:

• Misclassifying workers as independent contractors. California's ABC test under AB 5 presumes workers are employees unless specific conditions are met. Misclassification triggers back taxes, penalties, and interest on all four payroll taxes.
• Missing deposit deadlines. Late deposits incur penalties of 2% to 15% of the underpayment depending on how late the deposit is, plus interest.
• Incorrect withholding calculations. Using federal withholding tables instead of California tables, or failing to update withholding when employees submit new DE 4 forms.
• Failing to include S-Corp officer compensation. S-Corp shareholder-employees must be on payroll with proper withholding. Taking only distributions without salary is a major compliance violation.
• Not reconciling quarterly vs. annual totals. The sum of your four quarterly DE 9 filings must match your annual W-2 totals. Discrepancies trigger EDD notices and audits.
• Forgetting to file when there are no wages. Even if you had no payroll in a quarter, you may still need to file a "zero wage" return to avoid penalty notices.

How Payroll Integrates with S-Corp Elections

If you recently converted your LLC to an S-Corp, setting up payroll correctly is one of the most critical first steps. As an S-Corp shareholder-employee, your salary is subject to all the same payroll taxes as any other employee -- federal FICA (Social Security and Medicare), federal income tax withholding, California SDI, California PIT, and your company owes SUI and ETT on your wages.

The key benefit is that only your salary is subject to these taxes. Distributions above your reasonable salary are not subject to payroll taxes or self-employment tax. This is where the S-Corp tax savings come from, but only if you have properly set up payroll and are running it consistently.

We recommend running payroll at least monthly, even if you are the only employee. Irregular or annual lump-sum salary payments can raise red flags with the IRS and EDD. Consistency demonstrates that you are operating your S-Corp properly.

Getting Help with Payroll Compliance

California's payroll tax system is manageable for most small businesses, but the consequences of getting it wrong are significant. If you are setting up payroll for the first time or have questions about your obligations, schedule a free consultation with our team. We can help you choose the right payroll provider, set your reasonable compensation, and ensure your business entity is fully compliant with California and federal requirements.