What portion of unreimbursed employee business expenses are deductible for California taxpayers?

In California, unreimbursed employee business expenses are not deductible for state income tax purposes. This aligns with the current tax regulations, which state that while federal law may allow for certain deductions related to employee business expenses, California has opted to disallow these deductions for state tax filings. Therefore, the correct answer is that none of these expenses are deductible, making it clear why the option indicating that no portion is deductible for California taxpayers is accurate.

Other options, suggesting various percentages of deductibility, would imply that there could be some ability to claim deductions for these expenses, which is not the case under California tax law. Taxpayers in California should be aware of this distinction, especially since they might have different rules under federal taxation.