Information about Form W4, Employee's Withholding Certificate, including recent updates, related forms and instructions on how to file. Virginia Form VA-4 must be completed to know how much state income tax to withhold from your new employee's wages.Complete Form W-4 so that your employer can withhold the correct federal income tax from your pay. Use an online estimator to determine a specific amount to have your employer withhold each pay period. Resident Aliens (RA) may complete the W-4 and VA-4 just like a U.S. citizen. Please use the worksheet on both forms to calculate your allowances and exemptions.