In everyday terms, “who does taxes” can mean several different things, depending on what you’re asking. Here’s a clear breakdown focused on the United States context.

1. Who collects and enforces taxes?

At the federal level in the U.S., the government agency that administers and enforces most national taxes is the Internal Revenue Service (IRS) , which is part of the Department of the Treasury. The IRS processes federal tax returns, collects federal income and payroll taxes, helps taxpayers understand their obligations, and enforces tax laws when people don’t file or underpay.

Besides the IRS, there are other specialized federal tax bodies: taxes on alcohol, tobacco, and firearms are handled by the Alcohol and Tobacco Tax and Trade Bureau (TTB), while customs duties on imports are handled by U.S. Customs and Border Protection. Each state also has its own tax department (often called a Department of Revenue or Department of Taxation) that oversees state-level taxes like state income tax or state sales tax.

2. Who actually prepares tax returns?

When people say “who does taxes,” they often mean: who fills out the forms and files the returns. In practice, several types of people and services do this:

  • You, the taxpayer
    • Many individuals prepare and file their own returns using do‑it‑yourself software or official tax forms.
  • Paid tax professionals
    • Certified Public Accountants (CPAs), Enrolled Agents (EAs), and tax attorneys often prepare returns, especially for more complex situations such as businesses, multiple income sources, or complicated deductions.
  • National tax-prep chains
    • Large companies offer in‑person and online filing services, marketing themselves on convenience and “max refund” guarantees.
  • Tax software platforms
    • Online tools allow you either to fill out your return yourself or have a human expert review or complete it for you, often emphasizing accuracy and ease of use.

These preparers don’t “collect” the tax money; they help you calculate the correct amounts and submit your filings. The actual collection is still done by the IRS and the relevant state or local tax agencies.

3. Who sets the rules for taxes?

The rules for federal taxes in the U.S. come primarily from Congress, which has the constitutional power to “lay and collect taxes” and has codified tax law in the Internal Revenue Code. The Department of the Treasury issues regulations interpreting these laws, and the IRS publishes guidance and administers them in day‑to‑day practice. States pass their own tax laws under their own constitutions, which are then implemented by state tax agencies.

4. Putting it all together

If you’re asking “who does taxes” in the broad, civic sense, then:

  • Legislatures (Congress and state legislatures) write tax laws.
  • Agencies like the IRS and state tax departments administer and enforce them.

If you’re asking “who does taxes” in the practical, personal sense, then:

  • Individuals, tax professionals, and software or preparation companies prepare returns and help you file, while government agencies handle the official processing and collection.