A California SEIN number is the eight-digit State Employer Identification Number the Employment Development Department (EDD) assigns to every business that hires employees in California. It functions as your state payroll tax account number, tying your business to the unemployment insurance contributions, disability insurance, and income tax withholding you owe the EDD. It is separate from the federal EIN issued by the IRS, and if you employ workers in California you need both.1Employment Development Department. Am I Required to Register as an Employer?
Who Needs to Register
Any business that pays more than $100 in wages to one or more employees during a calendar quarter must register with the EDD and get a SEIN. Household employers, meaning people who hire nannies, housekeepers, or in-home caregivers, have a higher threshold: $750 or more in cash wages in a calendar quarter.1Employment Development Department. Am I Required to Register as an Employer?
Once you cross either threshold, you have 15 days to register.2California Legislative Information. California Code UIC – 1086 That clock starts the moment wages are paid, not when you decide to hire. Missing the window can trigger penalties, so register as soon as you know you will have employees.
Worker classification matters here. California uses the ABC test under AB 5 to decide whether a worker is an employee or an independent contractor. If someone you treat as a contractor actually qualifies as an employee under that test, you owe payroll taxes on their wages and need a SEIN to report them.3Employment Development Department. Employee or Independent Contractor The EDD audits for misclassification, and back taxes plus penalties add up quickly.
How to Register for a SEIN
The fastest route is online through the EDD’s e-Services for Business portal, which is available around the clock. Create an account, enter your business information, and the system issues your eight-digit SEIN once the registration processes.4Employment Development Department. e-Services for Business
If you prefer paper, complete Form DE 1 (the Commercial Employer Registration form) and mail it to EDD, Account Services Group, MIC 28, PO Box 826880, Sacramento, CA 94280-0001, or fax it to 916-654-9211.5Employment Development Department. Instructions for Completing the Commercial Employer Registration Form (DE 1) Paper takes longer to process, and given the 15-day deadline, online is the safer choice.
Have these ready when you register:
- Your federal EIN
- Your legal business name and address
- Your business entity type
- The date you first paid wages
The EDD asks for your federal EIN so it can match your state unemployment tax payments against your federal FUTA return.1Employment Development Department. Am I Required to Register as an Employer?
Household Employer Option
If you hire household workers and pay $20,000 or less in total household wages per year, you can elect annual tax filing instead of the standard quarterly schedule by completing the Employer of Household Worker Election Notice (DE 89). You still file wage reports each quarter, but you pay the actual taxes once a year. If your wages exceed $20,000 during the year, notify the EDD immediately and switch to quarterly payments.6Employment Development Department. Household Employer
What Your SEIN Tracks
Once you have the number, four state payroll taxes flow through it. Two are paid by the employer; two are withheld from employee wages.
- Unemployment Insurance (UI), employer-paid. For 2026, rates range from 1.5 percent to 6.2 percent under Schedule F+, which includes a 15 percent emergency surcharge. The taxable wage base is $7,000 per employee per year. New employers pay a standard rate until they build enough claims history for the EDD to calculate an individual experience rating.7Employment Development Department. Tax-Rated Employers
- Employment Training Tax (ETT), employer-paid at 0.1 percent on the first $7,000 of each employee’s wages.7Employment Development Department. Tax-Rated Employers
- State Disability Insurance (SDI), withheld from employee pay at 1.3 percent for 2026. Since January 1, 2024, all wages are subject to SDI; the taxable wage ceiling was eliminated.8Employment Development Department. Contribution Rates, Withholding Schedules, and Meals and Lodging Values
- Personal Income Tax (PIT) withholding, based on each employee’s W-4 or DE 4 allowances and the EDD withholding schedules.1Employment Development Department. Am I Required to Register as an Employer?
Quarterly Filing Once You Have the Number
Every quarter, you file two forms using your SEIN. The Quarterly Contribution Return and Report of Wages (DE 9) reconciles total wages paid against your tax liability. The companion form (DE 9C) lists each employee’s individual wages and PIT withholding. Both are filed together.9Employment Development Department. Required Filings and Due Dates
Electronic filing is mandatory. You submit the DE 9, DE 9C, and payroll tax deposits through e-Services for Business. Paper filing carries a noncompliance penalty of $50 per paper DE 9 and $20 per employee on a paper DE 9C.10Employment Development Department. 2025 California Employer’s Guide (DE 44)
For 2026, the quarterly filings are delinquent after:
- First quarter (January through March): April 30, 2026
- Second quarter (April through June): July 31, 2026
- Third quarter (July through September): November 2, 2026
- Fourth quarter (October through December): February 1, 202711Employment Development Department. Payroll Tax Calendar
Penalties for Missing a Deadline
Late payroll tax payments carry a 15 percent penalty plus interest. The interest rate resets every six months based on short-term federal rates; for the first half of 2026, it is 7 percent.12Employment Development Department. Interest Rate on Overdue Taxes
Wage reports that arrive late or missing employees cost $20 per employee per affected quarter. If you underpay your tax deposit before filing the DE 9, the penalty is 15 percent of the underpaid amount.10Employment Development Department. 2025 California Employer’s Guide (DE 44) Even for a modest payroll, one missed quarter can produce a penalty bill that outweighs the underlying tax.
Finding a Lost SEIN
If you have already registered but cannot locate your number, log in to your e-Services for Business account. The SEIN appears on the account dashboard and on any prior EDD correspondence or tax forms. Past DE 9 returns also show the eight-digit number near the top.
If you no longer have access to the online account or old documents, contact the EDD’s Taxpayer Assistance Center by phone. They can verify your identity and provide the account number. Have your federal EIN and business legal name ready.
Closing or Updating the Account
When you stop employing workers, you must formally close your EDD employer payroll tax account. The agency will keep expecting quarterly filings until you shut it down, and missed filings trigger penalties even if you owe zero tax.
Before closing, file your final DE 9 and DE 9C with any remaining payment within 10 days of the last payroll, regardless of the normal quarterly deadline.13Employment Development Department. Changes to Your Business Then close the account through e-Services for Business: log in, select “Close Account” from the Account Management Panel, enter the closure date and the date wages were last paid, choose a closure reason, and submit.
If your business changes entity type, for example from a sole proprietorship to an LLC, report that through the same portal by selecting “Update Account Information” and entering the date of the change. If you sell the business, the buyer should request a Certificate of Release of Buyer (DE 2220) from the seller before releasing escrow funds. That certificate confirms the seller has paid everything owed to the EDD.13Employment Development Department. Changes to Your Business