There are all sorts of various benefits to which an employee is entitled under either California or federal law (e.g., Social Security benefits, State Disability Insurance, unemployment, workers compensation, pregnancy leave, Family and Medical Leave, WARN Act pay, etc.).
However, there is no law requiring that an employer provide ERISA, group health care, vacation, sick leave, etc., regardless of whether or not the employee is part or full time.
The only requirements under California law are that an employee cannot be required to work seven consecutive days, work without a meal break after four hours, or without at least one 10 minute rest break for each four hours of work.
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