Taxes 101 What Is Income Tax? Read the Article Open Share Drawer Share this:Click to share on Facebook (Opens in new window)Click to share on Twitter (Opens in new window)Click to share on LinkedIn (Opens in new window)Click to share on Pinterest (Opens in new window)Click to print (Opens in new window) Written by Philip Taylor Published Nov 16, 2010 - [Updated Feb 11, 2025] 7 min read Reviewed by Lena Hanna, CPA Income tax is the biggest tax the average individual pays in the US. This tax is based on the amount of income you earn each year and is applied on a progressive basis. Generally, this means that the more you earn, the higher your taxes will be. Whether you work at a grocery store or own a small business, taxes are something we all have to deal with. To help you get a foundational understanding of how income taxes work, we’ll explain the basics of why you pay them, how you’ll be taxed, and how you file. Table of Contents Key takeawaysWhy do we pay income tax?History of income taxes in the USHow do income taxes work?Are there any exemptions from income tax?How are income taxes reported to the IRS? Key takeaways What are income taxes? Taxes paid on taxable income, which includes items such as wages, self-employment earnings, investments, unemployment benefits, and gambling winnings. The majority of income is taxable, unless exempt by law. Why do we pay income taxes? Income taxes help support government initiatives and fund essential services. How is income taxed? Income taxes are based on a progressive tax system that applies different tax rates to the portion of your income that falls into corresponding tax brackets. How do you file income taxes? You’ll typically use Form 1040 to file your personal income taxes. When are income taxes due? Income taxes must be filed by April 15 unless you get an extension. Why do we pay income tax? Income tax exists for the same reason many other taxes do: It’s used to fund the federal government. The income taxes you pay contribute to funds that are used to pay for highways, essential programs to support other citizens, the defense budget, and more. If you’re a first-time filer, you might only be familiar with federal taxes, but your income may also be taxed by your state, city, or county. It’s important to understand your state tax laws and what taxes might apply to you based on where you live so you can properly estimate how much you’ll owe and prepare accordingly. History of income taxes in the US While income taxes are an essential part of how we fund government initiatives today, that wasn’t always the case. In fact, income taxes have only existed for a little more than a century in the US. Let’s take a quick look at some of the history of federal income taxes in the US: In 1913, the 16th Amendment to the Constitution was ratified, resulting in the first permanent federal income tax for the US. Initially, income tax rates were between 1% and 7% and were collected annually. Throughout history, the top tax bracket has been raised significantly in response to events such as World War I and World War II. For example, in 1932, in response to the Great Depression, it was raised to 63% for individuals earning over $1 million. In 1942, the Revenue Act of 1942 was passed, which resulted in more people qualifying for income taxes. In 1943, the withholding tax was introduced under the Current Tax Payment Act to ensure employers withheld income taxes from employees. As you can see, throughout history, income tax policies have evolved, with much larger swings in income tax rates. In recent history, from 2018 to the present day, income tax rates have remained the same, with brackets changing slightly to accommodate inflation and changes in the cost of living. How do income taxes work? There are several types of income taxes, and income tax rates can change significantly based on how much you make. Let’s take a closer look at the different types of income taxes in the United States and what you need to know as a taxpayer. What are the types of income tax in the United States? Personal federal income taxes may be the first thing that comes to mind when you think about income taxes, but there are a few important distinctions you can make. Personal vs. business income Most people pay personal income tax, which is based on the income you earn as an employee or self-employed individual. However, if you own a business, you may also have to pay corporate taxes or business income taxes, depending on the tax structure of your business. Federal vs. state While the federal government has the highest income tax rates, they’re not the only ones that levy taxes. Many state and local jurisdictions also levy taxes, which means your total income tax rate may vary depending on your location. It’s important to check your state’s tax authority policies to understand what you may owe. Fortunately for some, there are several states that have no state income taxes, including: Alaska Florida South Dakota Tennessee Texas Washington Wyoming Additionally, New Hampshire only applies income taxes to dividends and interest. Although these states do not impose income tax, they do have sales tax and other types of taxes. Investments and unemployment Income tax isn’t just levied on salaries and wages. Anything that’s considered taxable income is subject to the income tax, which includes things like capital gains, income from dividend payments, and unemployment benefits. What’s considered taxable income? Anything that’s considered taxable income should be reported on your tax return so you can ensure everything is accounted for in your final tax bill. There are a few rules you should know regarding what’s considered taxable vs. nontaxable income. Earnings Wages and employee benefits are the most common forms of taxable income, but income from self-employment and side jobs is also taxable. This includes: Income from gig work or side jobs Renting out personal property Selling goods and services online Working as an independent contractor Some investments Various types of investments are also subject to income taxes, including: Capital gains Stock options and stock trades Interest and dividends Disposing or receiving digital assets and cryptocurrency Keep in mind that capital losses can be used to offset capital gains, reducing your tax liability. Other types of income can also be subject to income tax, including certain: Prizes and rewards Gambling winnings Canceled debts Court awards and damages Royalties and rent received Certain benefits You also may be liable to pay income taxes on: Social Security income Unemployment benefits Certain life insurance proceeds Retirement plan distributions If you need help determining whether the earnings, benefits, and money you’ve received qualify as taxable income, a tax professional can help you navigate the requirements. Calculating your taxable income correctly is necessary to help you determine your adjusted gross income (AGI) and modified adjusted gross income (MAGI). How much are income taxes? Your income taxes are calculated based on your filing status and the rates that apply to which tax brackets portions of your income fall into. Are there any exemptions from income tax? There are certain exemptions from income tax that you may be eligible for, but you have to meet specific requirements. Some businesses may be tax-exempt if they’re considered nonprofit organizations. Additionally, qualifying charitable organizations, churches and religious organizations, private foundations, political organizations, and other nonprofits may be able to file exempt. If your standard or itemized deduction exceeds your income or your income is exempt (such as certain Veteran’s disability benefits) or eligible for exclusion (such as some income earned from work abroad) you may not have to pay income taxes. However, you are likely to still need to file an income tax return to demonstrate that your tax liability is zero. Exceptions to be required to file apply if you don’t meet certain filing thresholds. How are income taxes reported to the IRS? If you’re an employee, your employer will withhold your income taxes and send you a W-2 after the end of the year. You can use the information from your W-2 to complete your personal tax return. Self-employed individuals are responsible for withholding their own taxes to pay estimated quarterly taxes. Estimated quarterly taxes are due on: April 15 June 15 September 15 January 15 If any of these dates falls on a weekend or federal holiday, the due date is the following business day. Your personal tax return is due on April 15, whether you’re self-employed or an employee. You’ll use Form 1040 to calculate your income taxes and file your return. If you need assistance completing your tax return, a tax expert can answer your questions or even do it for you to simplify the process. Previous Post What are Federal Taxes & Why Do We Pay Them? Next Post What Are Tax Brackets? 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