Form W-4

• Employers are responsible for having employees fill out W-4 forms when they start their jobs. An employee should also fill out an updated W-4 form if his filing situation changes --- if he marries, for example, or has a child. Form W-4 asks for information about an employee's filing status, such as whether he is married or single. It also asks for the number of withholding exemptions that he believes will correspond with his tax liability. The higher the number of exemptions you claim, the less your employer will withhold from your paychecks.
  
  

Social Security and Medicare

• Employers are responsible for withholding Social Security and Medicare taxes from employee paychecks. As of 2011, the tax rate for Social Security withholding is 4.2 percent of an employee's gross earnings, and the tax rate for Medicare withholding is 1.45 percent of her gross earnings. Unlike federal income tax withholding rates, the rate that employees must pay for Social Security and Medicare taxes does not generally vary with income level, although individual earnings in excess of $106,800 per calendar year are not subject to Social Security tax withholding as of 2011.
  
  

Income Tax Withholding

• The information that you provide for your employer on your Form W-4 corresponds to fields on tax tables that the IRS sends to employers at the beginning of each calendar year. These tables are also available online. Tax tables contain pages for each type of filing status, such as married or single, as well as pages corresponding to different pay periods, such as weekly or monthly. Each page also contains columns corresponding to numbers of withholding allowances as well as lines for different wage ranges. To determine your federal income tax liability, you employer finds the line and column that corresponds to your gross wages on the page that matches your filing status.
  
  

Tax Withholding Payments

• Your employer must remit the amounts of tax withholding that he has deducted from your paychecks according to a schedule that the IRS provides for him when he registers as an employer. Most business bank accounts can be linked to an online federal tax payment system in order to make electronic employment tax payments. He must also fill out quarterly employment tax forms reconciling his liability with his payments.