The quickest way to find a California employer state ID number is to look at Box 15 of any W-2 the employer has issued. That box shows “CA” followed by the eight-digit State Employer Identification Number (SEIN) assigned by the Employment Development Department. If you don’t have a W-2, the number also sits at the top of the employer’s quarterly payroll filings, and employers looking up their own number can retrieve it through the EDD’s e-Services for Business portal.
What the Number Looks Like
The SEIN is an eight-digit account number formatted 000-0000-0, issued by the EDD when a business registers as an employer in California.1Employment Development Department. Am I Required to Register as an Employer? It is not the Federal EIN, which is a separate nine-digit number issued by the IRS.2Internal Revenue Service. Employer Identification Number The EDD uses the SEIN to track an employer’s contributions for Unemployment Insurance, State Disability Insurance, Employment Training Tax, and Personal Income Tax withholding.
Check the Paperwork You Already Have
Before calling any agency, look at the documents in your own files. The number is not confidential from the employer’s own workers, and it appears in a few predictable places.
Box 15 of Your W-2
Every California employer that pays wages must report its state ID number in Box 15 of the W-2, next to the “CA” state abbreviation.3Internal Revenue Service. 2026 General Instructions for Forms W-2 and W-3 Any W-2 from the employer works. The SEIN doesn’t change year to year, so an older copy is fine. Employers must send W-2s to employees by January 31.
Quarterly Payroll Filings (DE 9 and DE 9C)
Employers file a Quarterly Contribution Return (DE 9) and a wage report (DE 9C) with the EDD every three months. Both list the employer account number at the top of the form. If you handle payroll or accounting for the business, these are the most reliable internal source.
Ask Payroll
Payroll staff use the SEIN constantly and can hand it over. For a current or former employee with a reason to need it, a direct request is often faster than any state lookup.
Retrieving Your Own SEIN as an Employer
If you run the business, the EDD’s e-Services for Business portal is the direct route. Signing in with the username and password you created at registration gives you access to your account details, including the account number, along with the ability to file returns, adjust them, and make tax deposits.4Employment Development Department. e-Services for Business
If you registered on paper and never set up online access, you can enroll through the same portal by selecting “Enroll,” entering your information, and verifying your email within 24 hours.5Employment Development Department. Employers: Payroll Tax Account Registration Your SEIN and account history are available once enrollment is complete.
Looking Up Another Company’s SEIN
This is the harder case. The EDD does not publish a public directory where you can type in a business name and get a SEIN back. Privacy rules limit who can obtain the number and why.
The EDD’s Taxpayer Assistance Center is the place to start if you have a legitimate reason, such as an active unemployment or disability claim tied to that employer. Bring the employer’s exact legal name, business address, and Federal EIN to the call. Whether the EDD will confirm the SEIN depends on your relationship to the employer and whether the agency can verify your identity.
Two other state lookups don’t return the SEIN itself but help you build the file you need before you call.
Secretary of State bizfile Online
The California Secretary of State’s bizfile Online tool searches corporations, LLCs, and limited partnerships by name at no cost.6California Secretary of State. Search | California Secretary of State – bizfile Online It gives you the entity’s exact registered legal name (small spelling differences cause matches to fail at the EDD), the SOS entity ID number, and the entity’s status: active, suspended, or dissolved.
Franchise Tax Board Entity Status Letter
The FTB’s Self Serve Entity Status Letter tool at webapp.ftb.ca.gov lets you check whether a corporation or LLC is in good standing for state tax purposes. A business the FTB has suspended for unpaid franchise or income taxes cannot legally transact business in California, which is a useful signal about whether its EDD registration is likely current.
Gather This Before You Call the EDD
To keep the inquiry from stalling on a name mismatch, pull these details together first:
- The entity’s exact legal name, including “Inc.” or “LLC,” confirmed against bizfile Online
- The SOS entity ID: a seven-digit corporation number or a nine- to twelve-digit LLC number5Employment Development Department. Employers: Payroll Tax Account Registration
- The Federal EIN, which state systems often use as a secondary identifier
- The physical business address, useful when the company name is common
- The entity type (corporation, LLC, partnership) so the representative can search the right record
When No Number Turns Up
An empty result is itself information. A newly formed business that registered with the Secretary of State but hasn’t yet hired anyone may not have an EDD account. California employers must register with the EDD within 15 days of paying more than $100 in wages in a calendar quarter, or $750 for household employers.1Employment Development Department. Am I Required to Register as an Employer? Below that threshold, no SEIN exists yet.
A business that has dissolved or voluntarily wound down will have an inactive SEIN, and the SOS and FTB status checks will usually explain the gap.
If you are an employee and the employer refuses to give you the SEIN, treat that as a warning. The number appears on every W-2 and every quarterly filing, so there is nothing to withhold. An employer who won’t share it may not be registered with the EDD, which raises the question of whether the state payroll taxes withheld from your wages are actually being paid over.