There is no specific tax ID number or a specific unemployment tax ID number for California. Instead every individual has their own Tax ID which is usually his/her Social Security Number. This the nine-digit number that identifies you personally. Its format is XXX-XX-XXXX, and no two people have the same number. If you are looking for a business tax ID number this is separate and is called an Employment Identification Number (EIN). The EIN can be used to identify a business entity that is legally separate and generally businesses need one.The state's tax ID number can usually be found in the state withholding documents or worksheet booklet where the ID number is listed on the payment vouchers. In most states, including California, the State ID number is the same as the Federal ID number. For more information with the tax ID number for California it would be visiting this government site - www.ftb.ca.gov/individuals/index.shtml For information regarding unemployment in California you should visit this site - www.edd.ca.gov/, which will give you information on what benefits unemployed people can get in the state and will always give you the information you need in terms of an unemployment tax ID if one actually exists. If you need a new tax ID number for California you are able to apply for one online, mail the forms in or even do it in person by visiting your local state board of equalisation. There is no fee for getting a tax ID as they want to make it easy for you to pay them tax. The whole process can be all done within 20 minutes and you will be the proud owner of California tax ID which can be used immediately afterwards.