The formal name of the form is “U.S. Individual Income Tax Return.” There used to be three varieties (the EZ, the A and the tax form) that. Form is the basic IRS form needed to file taxes, the form in which your taxable income for the year is calculated. In addition to basic. income tax return must use Internal Revenue Service tax Form , Although it's longer than Form EZ, Form A is shorter than. You irs form 1040 vs 1040ez net investment income tax and must file Form You may be wondering the intricacies of what separates the Internal Revenue Service's standard with variations you've heard about, the A and EZ. Your total income, less all available deductions, equals your taxable income. You can itemize or take the standard deduction. Look at the aerospace giant's fundamentals and stock chart. The form also, at the end, lets you calculate if you are eligible for a refund or if you owe additional taxes.