Updated to reflect federal income tax withholding changes for expatriates and nonresident aliens due to the new federal Form W-4, effective January 1, 2020.
Employers may use IRS Publication 15-T, Federal Income Tax Withholding Methods, to figure the amount of federal income tax to withhold from their employees' wages.
HR guidance on compliance with payroll taxes, including income taxes, Social Security and Medicare (FICA) taxes, and unemployment, disability and workers' compensation insurance taxes.