This chapter discusses the following topics.

• Whether you have to file a return.
• Which form to use.
• How to file electronically.
• When, how, and where to file your return.
• What happens if you pay too little or too much tax.
• What records you should keep and how long you should keep them.
• How you can change a return you have already filed.

You must file a federal income tax return if you are a citizen or resident of the United States or a resident of Puerto Rico and you meet the filing requirements for any of the following categories that apply to you.

1. Individuals in general. (There are special rules for surviving spouses, executors, administrators, legal representatives, U.S. citizens and residents living outside the United States, residents of Puerto Rico, and individuals with income from U.S. possessions.)
2. Dependents.
3. Certain children under age 19 or full-time students.
4. Self-employed persons.
5. Aliens.

The filing requirements for each category are explained in this chapter.

The filing requirements apply even if you do not owe tax.

If you are a U.S. citizen or resident, whether you must file a return depends on three factors:

1. Your gross income,
2. Your filing status, and
3. Your age.

To find out whether you must file, see Table 1-1, Table 1-2, and Table 1-3. Even if no table shows that you must file, you may need to file to get money back. (See Who Should File, later.)

This includes all income you receive in the form of money, goods, property, and services that is not exempt from tax. It also includes income from sources outside the United States or from the sale of your main home (even if you can exclude all or part of it). Include part of your social security benefits if:

1. You were married, filing a separate return, and you lived with your spouse at any time during 2012; or
2. Half of your social security benefits plus your other gross income and any tax-exempt interest is more than $25,000 ($32,000 if married filing jointly).

If either (1) or (2) applies, see the instructions for Form 1040 or 1040A, or Publication 915, Social Security and Equivalent Railroad Retirement Benefits, to figure the social security benefits you must include in gross income.

Common types of income are discussed in Part Two of this publication.

If you are married and your permanent home is in a community property state, half of any income described by state law as community income may be considered yours. This affects your federal taxes, including whether you must file if you do not file a joint return with your spouse. See Publication 555, Community Property, for more information.

A registered domestic partner in Nevada, Washington, or California (or a person in California who is married to a person of the same sex) generally must report half the combined community income of the individual and his or her domestic partner (or California same-sex spouse). See Publication 555.

If you are self-employed, your gross income includes the amount on line 7 of Schedule C (Form 1040), Profit or Loss From Business; line 1 of Schedule C-EZ (Form 1040), Net Profit From Business; and line 9 of Schedule F (Form 1040), Profit or Loss From Farming. See Self-Employed Persons, later, for more information about your filing requirements.

Your filing status depends on whether you are single or married and on your family situation. Your filing status is determined on the last day of your tax year, which is December 31 for most taxpayers. See chapter 2 for an explanation of each filing status.

If you are 65 or older at the end of the year, you generally can have a higher amount of gross income than other taxpayers before you must file. See Table 1-1. You are considered 65 on the day before your 65th birthday. For example, if your 65th birthday is on January 1, 2013, you are considered 65 for 2012.

You must file a final return for a decedent (a person who died) if both of the following are true.

• You are the surviving spouse, executor, administrator, or legal representative.
• The decedent met the filing requirements at the date of death.

For more information on rules for filing a decedent's final return, see Publication 559, Survivors, Executors, and Administrators.

To determine whether you must file a return, include in your gross income any income you received abroad, including any income you can exclude under the foreign earned income exclusion. For information on special tax rules that may apply to you, see Publication 54, Tax Guide for U.S. Citizens and Resident Aliens Abroad. It is available online and at most U.S. embassies and consulates. See How To Get Tax Help in the back of this publication.

If you are a U.S. citizen and also a bona fide resident of Puerto Rico, you generally must file a U.S. income tax return for any year in which you meet the income requirements. This is in addition to any legal requirement you may have to file an income tax return with Puerto Rico.

If you are a bona fide resident of Puerto Rico for the entire year, your U.S. gross income does not include income from sources within Puerto Rico. It does, however, include any income you received for your services as an employee of the United States or a U.S. agency. If you receive income from Puerto Rican sources that is not subject to U.S. tax, you must reduce your standard deduction. As a result, the amount of income you must have before you are required to file a U.S. income tax return is lower than the applicable amount in Table 1-1 or Table 1-2. For more information, see Publication 570, Tax Guide for Individuals With Income From U.S. Possessions.

If you had income from Guam, the Commonwealth of the Northern Mariana Islands, American Samoa, or the U.S. Virgin Islands, special rules may apply when determining whether you must file a U.S. federal income tax return. In addition, you may have to file a return with the individual island government. See Publication 570 for more information.

If you are a dependent (one who meets the dependency tests in chapter 3), see Table 1-2 to find whether you must file a return. You also must file if your situation is described in Table 1-3.

Generally, a child is responsible for filing his or her own tax return and for paying any tax on the return. If a dependent child must file an income tax return but cannot file due to age or any other reason, then a parent, guardian, or other legally responsible person must file it for the child. If the child cannot sign the return, the parent or guardian must sign the child's name followed by the words "By (your signature), parent for minor child."

Amounts a child earns by performing services are included in his or her gross income and not the gross income of the parent. This is true even if under local law the child's parent has the right to the earnings and may actually have received them. But if the child does not pay the tax due on this income, the parent is liable for the tax.

If a child's only income is interest and dividends (including capital gain distributions and Alaska Permanent Fund dividends), the child was under age 19 at the end of 2012 or was a full-time student under age 24 at the end of 2012, and certain other conditions are met, a parent can elect to include the child's income on the parent's return. If this election is made, the child does not have to file a return. See Parent's Election To Report Child's Interest and Dividends in chapter 30.

You are self-employed if you:

• Carry on a trade or business as a sole proprietor,
• Are an independent contractor,
• Are a member of a partnership, or
• Are in business for yourself in any other way.

Self-employment can include work in addition to your regular full-time business activities, such as certain part-time work you do at home or in addition to your regular job.

You must file a return if your gross income is at least as much as the filing requirement amount for your filing status and age (shown in Table 1-1). Also, you must file Form 1040 and Schedule SE (Form 1040), Self-Employment Tax, if:

1. Your net earnings from self-employment (excluding church employee income) were $400 or more, or
2. You had church employee income of $108.28 or more. (See Table 1-3.)

Use Schedule SE (Form 1040) to figure your self-employment tax. Self-employment tax is comparable to the social security and Medicare tax withheld from an employee's wages. For more information about this tax, see Publication 334, Tax Guide for Small Business.

If you are a U.S. citizen who works in the United States for an international organization, a foreign government, or a wholly owned instrumentality of a foreign government, and your employer is not required to withhold social security and Medicare taxes from your wages, you must include your earnings from services performed in the United States when figuring your net earnings from self-employment.

You must include income from services you performed as a minister when figuring your net earnings from self-employment, unless you have an exemption from self-employment tax. This also applies to Christian Science practitioners and members of a religious order who have not taken a vow of poverty. For more information, see Publication 517, Social Security and Other Information for Members of the Clergy and Religious Workers.

Your status as an alien—resident, nonresident, or dual-status—determines whether and how you must file an income tax return.

The rules used to determine your alien status are discussed in Publication 519, U.S. Tax Guide for Aliens.

If you are a resident alien for the entire year, you must file a tax return following the same rules that apply to U.S. citizens. Use the forms discussed in this publication.

If you are a nonresident alien, the rules and tax forms that apply to you are different from those that apply to U.S. citizens and resident aliens. See Publication 519 to find out if U.S. income tax laws apply to you and which forms you should file.

If you are a resident alien for part of the tax year and a nonresident alien for the rest of the year, you are a dual-status taxpayer. Different rules apply for each part of the year. For information on dual-status taxpayers, see Publication 519.

Even if you do not have to file, you should file a federal income tax return to get money back if any of the following conditions apply.

1. You had federal income tax withheld or made estimated tax payments.
2. You qualify for the earned income credit. See chapter 35 for more information.
3. You qualify for the additional child tax credit. See chapter 33 for more information.
4. You qualify for the health coverage tax credit. See chapter 36 for more information.
5. You qualify for the refundable credit for prior year minimum tax.
6. You qualify for the American opportunity credit. See chapter 34 for more information.
7. You qualify for the credit for federal tax on fuels. See chapter 36 for more information.