Common IRS Tax Forms Find Common Tax Forms See this list of the most common IRS tax forms, including 1040, W2, W4, 1098 & 1099. Learn more about each and find out if you need to use them this year. 1040EZ Series for Individuals Taxpayers with income under $100,000 might qualify to use this simplified tax form. 1040 Tax Form 1040EZ Read more about 1040 form here. 1040A Series for Individuals Most taxpayers are eligible to file this shorter tax form. Income under $100,000, can claim dependents, can use any filing status, and can claim some adjustments to income. This form is the best place to start for most people. 1040 1040A 1040A Form The IRS Form 1040A is one of three forms you can use to file your federal income tax return. Form 1040A is a shorter version of the more detailed Form 1040, but is more complex than the simple 1040EZ form. All taxpayers can use Form 1040; however, to use Form 1040A you must satisfy a number of requirements, such as having taxable income of $100,000 or less and claiming the standard deduction rather than itemizing. 1040 Series for Individuals Form 1040, the "long form," covers all possible tax situations. Anyone at all can file this form. So if you're in doubt about which form to file, it's always a safe bet to stick to the 1040. 1040 Form Instructions Form 1040 DEFINITION of '1040 Form' The standard Internal Revenue Service (IRS) form that individuals use to file their annual income tax returns. The form contains sections that require taxpayers to disclose their financial income status for the year in order to ascertain whether additional taxes are owed or whether the taxpayer is due for a tax refund. 1040 forms need to be filed with the IRS by April 15.