I am a resident of TN but did a contract job from which I was paid through payroll working for a CA company. They have withheld CA SUI/SDI taxes over a period of a couple months. Are these taxes applicable to me as a non-california resident? Is there a way for me to apply for a refund of these withholdings? I know I will receive a refund on the CA state income taxes and am hoping these other monies can be returned to me as well! Thanks for any help!

They should be refunded to you, as they are California taxes. You need to contact the California Franchise Tax Board. You can find information on their rules for taxation here. Good luck to you!

Clearly they do NOT apply to you.

However, ask the EMPLOYER to refund the taxes first. There may still be time for them to adjust their final business return with California.

What is sui/sdi tax? Does that involve unemployment or disability insurance

CA State Disability Insurance. It is at 0.6%. Non CA residents do not pay it.

SUI is unemployment insurance.