Following tax law changes, you should do a paycheck checkup using the IRS’s Withholding Calculator and, if necessary, complete a new W-4 form. The calculator helps determine the right amount of withholding.
You should check if you:
- Are a two-income family.
- Have two or more jobs at the same time or only work part of the year.
- Claim credits like the child tax credit.
- Have dependents age 17 or older.
- Itemized deductions in 2017.
- Have high income or a complex tax return.
- Have a large tax refund or tax bill for 2017.
See IRS.gov/taxreform for more information.