The Form 1040 is the starting form for personal income tax returns filed in the United States. See Taxation in the United States. Any individual U.S. income taxpayer can use Form 1040 (the "long form"). Those with uncomplicated tax situations (for example, no itemized deductions, no capital gain or loss, etc.) may be able to use the simplified Form 1040A (the "short form") or the even simpler Form 1040EZ (the "easy form") instead of Form 1040.

Income tax returns for calendar year taxpayers are due by April 15 of the next year, or by the Monday following if April 15 falls on a Sunday.

Form 1040 is a two-page form; the first page collects information about the taxpayer(s), dependents, income items, and adjustments to income. The second page calculates the tax due, given the income figure, allowable deductions and credits, and applies funds already withheld from wages or estimated payments made towards the tax liability.

Form 1040 has 11 optional attachments, called "schedules".

Schedule A itemizess allowable deductions against income; instead of filling out Schedule A, taxpayers may choose to take a "standard deduction" of between $3925 and $9650, depending on age and filing status.

Schedule B enumerates interest or dividend income, and is required if either interest or dividends received during the tax year exceed $1500.

Schedule C lists income and expenses related to self-employment, and is used by sole proprietors. (Schedule C has a smaller version, the C-EZ, which is used for very simple self-employment situations.)

Schedule D is used to describe capital gains and losses incurred during the tax year, and to calculate the tax amount due given the special reduced tax rates applied to capital gains.

Schedule E is used to report income and expenses arising from the rental of real property, royalties, or from pass-through entities (like trusts, estates, partnerships, or S corporations).

Schedule EIC is used to document a taxpayer's eligibility for the Earned Income Credit.

Schedule F is used to report income and expenses related to farming.

Schedule H is used to report taxes owed due to the employment of household help.

Schedule J is used when averaging farm income over a period of several years.

Schedule R is used to calculate the Credit for the Elderly or the Disabled.

Schedule SE is used to calculate the self-employment tax owed on income from self-employment (such as on a Schedule C, or in a partnership).

In some situations, other IRS forms must be attached to the Form 1040, in addition to the Form 1040 schedules.

External link:

• United States Internal Revenue Service - includes downloadable forms and publications