Why did I not have federal income tax withheld?

You may not have had federal income tax withheld for several reasons, such as incorrectly filling out your W-4 form, claiming too many allowances, or indicating that you are exempt from withholding. Additionally, if you earned below the threshold for taxable income or are part of a specific category (like students or certain part-time workers), you might not have had taxes withheld. It's important to review your tax situation to ensure compliance and adjust your withholding if necessary.