Tax Form W-4 is used by an employer to withhold the proper amount of federal income tax from an employees’ paycheck. The IRS recommends that employees submit a new W-4 tax form each year, or any time their personal or financial situation changes. This is required upon being hired.
When a business pays an independent contractor $600 or more over the course of a tax year, it is required to report these payments to the IRS on an information return called form 1099-MISC. Businesses use the name, address and Social Security or tax identification number from form W-9 to complete form 1099-MISC.
Form 4868 is an automatic tax extension for individuals reporting their income to the IRS. This includes all taxpayers who file 1040's, contractors who file 1099's, as well as single-member LLC's and Schedule C Sole Proprietors.