2018 tax reform There is no longer a reduction(4,050 per person)to your Income for dependents. There is going to be a temporary credit of $500 per person not covered by the child tax credit. ie a spouse or parent you support.
If the w-4 allows you to add a % or $ additional payment from each check use that.
Disclaimer: Not a tax professional. Information gathered from internet links. Anything dated in June 2019 was posted in prior years and is before the 2019 limits and changes.
