Kentucky has a flat income tax rate of 5% and withholding tax exemptions are not allowed on Form K-4, Kentucky Withholding Certificate. There are four categories under which an employee may claim exempt from withholding on Form K-4. See Employee's Withholding Allowance Certificate. Tax on suppl...
Step 4b: any additional withholding you want taken out. Any other estimated tax to withhold can be entered here. The more is withheld, the bigger your refund may be and you’ll avoid owing penalties. If your W4 on file is in the old format (2019 or older), toggle "Use new Form W-...