What Makes a W-4 Form Invalid


  • Missing social security number and/or missing name and address
  • Inaction in 1c (failure to mark a marital status)
  • Lack of signature at the bottom of the form
  • Completing and dating a form in the current year on a form from a previous year
    • The year of the form should match the year form is signed  


  • Missing social security number or other information
  • Marking a number of allowances in field 6 AND marking an exemption box in field 8 
    • Field 6 tells us how much to withhold for taxes and field 8 indicates not to withhold at all so if both are used the form is invalid
  • Failure to mark either field 6 or field 8
  • Lack of signature on the form