Taxation is the mandatory payment that federal, state, and local governments collect from individuals and businesses to fund public services such as roads, schools, national defense, and social programs. It is a legal obligation backed by enforceable penalties, not a voluntary contribution. In the United States, taxation shows up in several forms across a single year: income tax withheld from a paycheck, payroll taxes for Social Security and Medicare, sales tax at the register, property tax on a home, and excise taxes built into the price of fuel or tobacco.
Where the Power to Tax Comes From
The federal government’s authority to tax income comes from the Sixteenth Amendment to the U.S. Constitution, ratified in 1913, which gives Congress the power to collect taxes on income “from whatever source derived” without apportioning the burden among states by population.1Congress.gov. U.S. Constitution – Sixteenth Amendment Before the amendment, federal revenue leaned on tariffs and excise taxes. Today the income tax funds most federal operations.
State and local taxing powers come from state constitutions and statutes. State legislatures decide who owes tax, on what, and how much. Counties, cities, and school districts typically get their taxing authority from the state above them. Courts have consistently upheld these powers as a basic feature of organized government.
The Main Types of Taxes You Will Encounter
Individual Income Tax
Federal income tax uses a progressive structure. Higher portions of your income are taxed at higher rates, running through seven brackets from 10 percent up to 37 percent for tax year 2026.2Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026 The brackets work in layers, not as a flat rate on your whole income. A single filer earning $60,000 pays 10 percent on the first $12,400, 12 percent on the slice up to $50,400, and 22 percent only on the amount above that.3Internal Revenue Service. Federal Income Tax Rates and Brackets Most states layer their own income tax on top, though a handful have none.
Payroll and Self-Employment Taxes
If you draw a paycheck, payroll taxes fund Social Security and Medicare. You pay 6.2 percent of wages toward Social Security and 1.45 percent toward Medicare, and your employer matches both.4Office of the Law Revision Counsel. 26 USC 3101 – Rate of Tax The Social Security portion applies only to the first $184,500 of wages in 2026; the Medicare portion has no cap.5Social Security Administration. Contribution and Benefit Base Self-employed workers pay both halves, a combined 15.3 percent on net earnings, but can deduct the employer-equivalent half when calculating adjusted gross income.
High earners also owe an extra 0.9 percent Medicare surtax on wages above $200,000 for single filers or $250,000 for married couples filing jointly. Those thresholds are fixed by statute and do not adjust for inflation.4Office of the Law Revision Counsel. 26 USC 3101 – Rate of Tax
Sales and Excise Taxes
Sales tax is a percentage of the purchase price on goods and, in many places, services. Forty-five states charge a state sales tax, and local governments often add a surcharge, producing combined rates that range from under 3 percent to over 10 percent. Five states impose no state sales tax. Groceries, prescription drugs, and clothing are exempt in some jurisdictions.
Excise taxes target specific products such as gasoline, tobacco, and alcohol. They are usually built into the shelf price rather than added at the register. The federal excise tax on gasoline is 18.4 cents per gallon and flows into the Highway Trust Fund. States stack their own fuel taxes on top, and similar layered excises apply to cigarettes, beer, and spirits.
Property Tax
Property taxes fall on real estate — homes, land, commercial buildings — based on assessed value. A local assessor sets the value, and a local tax rate (sometimes called a millage rate) determines the bill. Revenue supports school districts, fire departments, road maintenance, and other community services. Rates and assessment methods vary widely because property tax is almost entirely a state and local matter. Nonpayment can lead to a lien on the property and, eventually, a forced sale.
Capital Gains Tax
When you sell an investment for more than you paid, the profit is a capital gain. Assets held one year or less are taxed at your regular income rates. Assets held longer than a year get long-term rates of 0, 15, or 20 percent depending on your taxable income. For 2026, a single filer pays 0 percent on long-term gains below $49,450 in taxable income, 15 percent up to $545,500, and 20 percent above that.6Internal Revenue Service. Revenue Procedure 2025-32 – 2026 Adjusted Items High-income taxpayers may also owe a 3.8 percent net investment income tax once modified adjusted gross income clears $200,000 (single) or $250,000 (married filing jointly).7Internal Revenue Service. Topic No. 559, Net Investment Income Tax
Estate and Gift Taxes
The federal estate tax applies to estates worth more than $15,000,000 per individual in 2026; anything below that threshold owes no federal estate tax.2Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026 Value above the exclusion is taxed on a graduated scale that tops out at 40 percent.8Office of the Law Revision Counsel. 26 USC 2001 – Imposition and Rate of Tax The gift tax works alongside the estate tax so people cannot avoid it by giving wealth away before death. Some states impose their own estate or inheritance taxes with lower exemption thresholds.
Corporate Income Tax
Corporations pay a flat federal income tax of 21 percent on taxable income, with no graduated brackets.9Office of the Law Revision Counsel. 26 USC 11 – Tax Imposed Most states also tax corporate income, and a few use a gross receipts tax instead.
How Deductions and Credits Reduce What You Owe
Before your tax is calculated, deductions reduce the income that gets taxed. The 2026 standard deduction is $16,100 for single filers, $32,200 for married couples filing jointly, and $24,150 for heads of household.2Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026 You can take the standard deduction or itemize deductible expenses like mortgage interest, charitable contributions, and state and local taxes if the total is higher. A $1,000 deduction saves you only the tax you would have paid on that $1,000.
Tax credits work differently. They reduce your tax bill dollar for dollar, so a $1,000 credit saves you exactly $1,000. Nonrefundable credits can bring your tax to zero but not below. Refundable credits, like the Earned Income Tax Credit, can generate a cash refund even when you owe no tax, which is why filing a return can pay off for lower earners.10Internal Revenue Service. Tax Credits for Individuals: What They Mean and How They Can Help Refunds
Who Collects and Enforces Taxes
Multiple governments can tax the same person or business at once. The Internal Revenue Service, operating under the Treasury Department, handles federal income tax collection and enforcement.11Internal Revenue Service. The Agency, Its Mission and Statutory Authority States run their own revenue departments for state income and sales taxes. Counties and municipalities focus on property taxes and local sales surcharges. A single paycheck can carry withholding for federal income tax, state income tax, Social Security, Medicare, and sometimes a local income or occupational tax.
Disputes with the IRS can be taken to the United States Tax Court, a federal court that hears only tax cases.12United States Tax Court. United States Tax Court State tax disputes go through that state’s own tribunal or court system.
Filing, Payment, and Penalties
The U.S. tax system runs on self-reporting. You calculate what you owe and file an annual return — Form 1040 for individuals — by the deadline.13Internal Revenue Service. About Form 1040, U.S. Individual Income Tax Return For most people the filing deadline for the 2025 tax year is April 15, 2026.14Internal Revenue Service. When to File Form 4868 buys an automatic six-month extension to file, but not to pay.15Internal Revenue Service. Form 4868, Application for Automatic Extension of Time to File U.S. Individual Income Tax Return Most tax is collected through the year — employer withholding for wage earners, quarterly estimated payments for the self-employed.
Miss the filing deadline and the failure-to-file penalty runs 5 percent of unpaid tax per month or partial month, capped at 25 percent.16Internal Revenue Service. Failure to File Penalty File on time but pay late and the failure-to-pay penalty is 0.5 percent per month, also capped at 25 percent. When both apply in the same month, the failure-to-file penalty is reduced by the failure-to-pay amount, so the combined hit is 5 percent rather than 5.5 percent.17Internal Revenue Service. Failure to Pay Penalty The IRS also charges interest on unpaid balances, set quarterly; for early 2026 the individual underpayment rate is 7 percent per year, compounding daily.18Internal Revenue Service. Quarterly Interest Rates Deliberate tax evasion can bring criminal prosecution, with fines and prison on the table. You are legally responsible for the accuracy of your return whether you prepared it or paid someone else to.
If you cannot pay in full, filing on time and requesting a payment plan is better than ignoring the bill. Taxpayers with an approved IRS installment agreement see the failure-to-pay penalty cut in half, from 0.5 percent to 0.25 percent per month, though interest still runs on the balance.17Internal Revenue Service. Failure to Pay Penalty Keep records supporting the income, deductions, and credits on your return for at least three years; seven years for a worthless-securities loss or bad-debt claim.19Internal Revenue Service. How Long Should I Keep Records
Your Rights as a Taxpayer
The IRS recognizes a Taxpayer Bill of Rights that outlines ten protections for anyone who deals with the tax system. Among them: the right to pay only the correct amount, the right to challenge IRS decisions and be heard, the right to appeal in an independent forum, and the right to finality, meaning the IRS cannot audit or collect indefinitely. You also have the right to hire a representative for any IRS interaction, and if you cannot afford one, a Low Income Taxpayer Clinic may be able to help.20Internal Revenue Service. Taxpayer Bill of Rights The Taxpayer Advocate Service, an independent organization inside the IRS, can step in when normal channels have not resolved an issue or when a tax problem is causing financial hardship.