Filing Requirements

Not everyone must file a tax return, but some of those people should. If withheld taxes or estimated payments exceed tax liability, then you must file to obtain a refund or to apply excess payments to the next tax year. People who can receive a payment from the government because of one or more refundable tax credits should also file. Refundable credits include the earned income credit, additional child tax credit, the refundable portion of the American opportunity educational credit, health insurance premium tax credit, and the credit for federal tax on fuels.

Filing Requirements Based on Income

Most people are required to file a tax return because the requirement kicks in when income reaches a very low level — too low for most people to live on. This is because the government needs to collect money from as many people as possible, so anyone who earns what Congress decided was enough, even though few people can live on such low incomes, must file a return and pay taxes.

The filing requirement income thresholds = the personal exemption + the basic standard deduction, and, if applicable, the additional standard deduction, although there are exceptions. (Note: the personal exemption = 0 until 2026 unless the current law is changed.) For instance, spouses filing separately must report income if it exceeds their personal exemption. If you are eligible for more than 1 filing status, then it makes sense to choose the filing status yielding the lowest tax.

Filing Requirement Income Thresholds
Filing Status Age at Year-End Income Income Income Income Income
2024 2023 2022 2021 2020
Single < 65 $14,600 $13,850 $12,950 $12,550 $12,400
≥ 65 $16,550 $15,700 $14,700 $14,250 $14,050
Head of
< 65 $21,900 $20,800 $19,400 $18,800 $18,650
≥ 65 $23,850 $22,650 $21,150 $20,150 $20,300
filing jointly
Both spouses < 65 $29,200 $27,700 $25,900 $25,100 $24,800
One spouse ≥ 65 $30,750 $29,200 $27,300 $26,450 $26,100
Both spouses ≥ 65 $32,300 $30,700 $28,700 $27,800 $27,400
filing separately
any age $5 $5 $5 $5 $5
Qualifying Surviving Spouse (QSS)
with dependent child
< 65 $29,200 $27,700 $25,900 $25,100 $24,800
≥ 65 $30,750 $29,200 $27,300 $26,450 $26,100

Filing Requirements for Dependents

There are also special filing requirements for dependents, depending on the taxpayer. The main differences from the regular requirements are that the income thresholds depend on whether the income is earned from work or unearned, which the IRS defines as income not earned from work, which applies to investment income, and whether the taxpayer is blind. Part of the reason for distinguishing between earned and unearned income is to determine whether the kiddie tax applies. More information: About Publication 501, Dependents, Standard Deduction, and Filing Information | Internal Revenue Service

Filing Requirements Based on Tax Liability or the Need to Report Information to the Federal Government

There are a few special situations where you may also have to file a return, regardless of income:

When Filing is Desirable, but Not Required

Sometimes, you may wish to file a tax return even if it is not required:

Tax Brackets

Below is a table listing the upper limits for the taxable income brackets, which applies to income after subtracting the standard deduction or itemized deductions. Each bracket span starts at the upper income limit for the lower bracket and ends at the specified amount for that bracket. So, for instance, for 2018, the 10% bracket applies to an income range from 0 to $9,525, while the 12% bracket applies to the following income range: $9,525 < Income ≤ $38,700.

The new Republican tax policy, passed at the end of 2017, known as the Tax Cuts and Jobs Act, has changed the tax brackets for 2018 and afterwards. Congruent to the Republicans' tax objective to benefit the wealthy, most of the benefits in the change to tax brackets go to those who earn more than $200,000. The marriage penalty has also been eliminated for all tax brackets, except the top 2.

The table below lists the upper limits for the income tax brackets. Remember, these income limits are based on taxable income, not gross income.

Upper Limits for Taxable Income Brackets
10% 12% 22% 24% 32% 35% 37%
Single $11,600 $47,150 $100,525 $191,950 $243,725 $609,350 Excess
HOH $16,550 $63,100 $100,500 $191,950 $243,700 $609,350
$23,200 $94,300 $201,050 $383,900 $487,450 $731,200
2 2 2 2 2 1.2 1
Single $11,000 $44,725 $95,375 $182,100 $231,250 $578,125 Excess
HOH $15,700 $59,850 $95,350 $182,100 $231,250 $578,100
$22,000 $89,450 $190,750 $364,200 $462,500 $693,750
2 2 2 2 2 1.2 1
  • Source:
  • Note: Married Filing Separately = 1/2 of Joint Rate

Note that the tax bracket for Married Filing Separately is always 1/2 of the MFJ bracket. For the 10% and 15% brackets, there is no marriage penalty, since the Married Filing Separately bracket is the same as the single bracket and MFJ is twice that amount. However, at higher brackets, there is a marriage penalty because the higher brackets start at lower income levels for married people than what would be implied by the corresponding Single bracket. In fact, the 33% and 35% tax brackets start at the same income levels for both Single and MFJ statuses. The top bracket also has a substantial marriage penalty, but it is a little better than a complete penalty. The irony here is that a couple in the 33% bracket suffers a higher penalty than a couple in the 35% bracket.

Tax Brackets Will Now Depend on the Chained-CPI

When prices go up, consumers search for cheaper, substitutable goods. The Consumer Price Index (CPI), often used as a measure of inflation, does not account for the substitution effect until several years later. This leads to a higher rate of inflation than actually experienced by most families. Consequently, the Bureau of Labor Statistics (BLS) developed a new measure of inflation called the Chained-CPI, which accounts for substitutions much more quickly, resulting in a lower percentage increase of inflation than measured by the CPI. This is illustrated by the following average inflation rates for December 2001 to December 2013 (Source: Bureau of Labor Statistics):

To reduce the increase in deficits incurred by the Republican tax policy passed at the end of 2017, this policy, known as the Tax Cuts and Jobs Act, links increases in the tax brackets to the Chained-CPI rather than the CPI used in the previous tax code. Thus, tax brackets will increase more slowly, causing taxes to creep higher relative to income over the following years.

Amended Tax Returns

If an already filed tax return has an error, then an amended return can be filed, on Form 1040X, Amended U.S. Individual Income Tax Return, which is used whether the original return was filed on Form 1040, 1040A, 1040EZ, 1040NR, or 1040NR-EZ. The filing deadline is the later of 3 years after the tax return was filed or within 2 years after the date the taxes were paid. There is no electronic filing option, only a paper filing, and a separate Form 1040X must be filed for different tax years. Additionally, documentation should be provided to explain the reason for the amendment and also any additional documents that would normally be required. Amended returns tend to be scrutinized more closely, which may result in a higher audit risk. Therefore, if the error is not serious, then it may be better to not file an amended return. If there is simply a math error, then the IRS either bill you for a shortfall or refund an overpayment.