Filing an income tax return is a yearly obligation for most U.S. citizens and residents. However, not everyone is required to file a return, and even some who do not have to file may want to do so for various reasons. Tax returns are due by a set date—generally April 15 for most individual taxpayers. It is possible to obtain an automatic six-month extension if action is taken in a timely manner. If not, penalties can apply. There are different versions of Form 1040, U.S. Individual Income Tax Return, for individuals. The version to use depends on the taxpayer's income, deductions, credits, and other factors. Special rules apply to individuals who are not U.S. citizens or residents.
In order to complete a return, you need to know certain personal information about a taxpayer. You must enter some of the information directly on the tax return; other information is useful to you as a preparer.