Which document serves as the source for Federal Tax tables?

The document that serves as the source for Federal Tax tables is Circular E. This publication is officially titled "Employer's Tax Guide" and provides essential information for employers regarding the withholding of Federal income tax from employee wages, as well as the related tax obligations for payroll. It includes detailed instructions on how to calculate the amount to withhold based on the employee's earnings and filing status, along with the current tax rates.

This resource is particularly important for employers to ensure compliance with federal tax laws and to aid in accurately processing employee paychecks. It also helps in understanding the various tax credits and adjustments that might affect withholding amounts. Thus, for anyone seeking guidance on federal income tax withholding for their payroll, Circular E is the authoritative resource.