The following is a recent message from UW-Madison OHR Payroll Services:
Dear UW-Madison Employee,
As a result of the Federal Tax Reform bill passed in December of 2017, many UW-Madison employees had a change in their federal income tax withholding beginning with the February 1st, 2018 paycheck. The new federal tax withholding is based on the updated tax tables from the IRS and the most recent form W-4 received. You can see your current tax withholding status and the number of the allowances you are claiming for federal and state in the upper right corner of your earnings statement in the box labeled “Tax Data”. Beneath that section under “Taxes” you can see your year to date (YTD) withholding as well as your per paycheck (current deductions) federal tax withholding.
The Internal Revenue Service (IRS) is encouraging taxpayers to make sure they are having the right amount of tax taken out of their paychecks. Doing a “paycheck checkup” can help prevent you from having too little or too much tax withheld. The IRS offers an online Withholding Calculator to help you determine the right amount of tax withholding for your situation. Find the IRS Withholding Calculator at irs.gov/individuals/irs-withholding-calculator. Taxpayers can also use the long form W-4 worksheet to determine the appropriate withholding status and number of allowances: https://www.irs.gov/pub/irs-pdf/fw4.pdf.
If you would like to make a change in how much federal income tax you have withheld from your paycheck, you will need to update your Form W-4, Employee’s Withholding Allowance Certificate. To fill out a new W-4, log into MyUW and launch the Payroll Information module or see your local payroll contact for assistance.
The IRS Website has more information: https://www.irs.gov/newsroom/irs-encourages-paycheck-checkup-for-taxpayers-to-check-their-withholding-special-week-focuses-on-changes