No, not legal.
In California, an employee who is discharged must be paid all of his or her wages, including accrued vacation, immediately at the time of termination. (Labor Code Sections 201 and 227.3.) However, an employee without a written employment contract for a definite period of time who gives at least 72 hours prior notice of his or her intention to quit, and quits on the day given in the notice, must be paid all of his or her wages, including accrued vacation, at the time of quitting. (Labor Code Section 202.)
The employer's failure to pay the final paycheck is a violation of the California Labor Code, and also subjects the employer to pay "waiting time penalties".
You can file a wage claim for the unpaid wages with the California Labor Commissioner. File the claim either by mail or in person with the Division of Labor Standards Enforcement (DLSE) office that handles wage claims for the city/location/community where the work was performed.
Frank W. Chen has been licensed to practice law in California since 1988. The information presented here is general in nature and is not intended, nor should be construed, as legal advice. This posting does not create any attorney-client relationship with the author. For specific advice about your particular situation, consult your own attorney.