The IRS is a federal agency, not a state one

The Internal Revenue Service (IRS) is part of the U.S. Department of the Treasury and operates at the federal level. It collects federal income taxes, which go to the federal government to fund national programs like Social Security, Medicare, defense, and infrastructure. The IRS does not work for your state — it works for the federal government.

This matters because the IRS handles different taxes than your state does. When you file taxes, you are actually filing two separate returns: one federal return to the IRS, and one state return to your state's tax agency (if your state has an income tax). They are different forms, sent to different places, and the money goes to different governments.

Key Takeaways

  • The IRS is a federal agency under the U.S. Department of the Treasury and collects federal income taxes only.
  • Most states run their own separate tax agencies and collect state income taxes independently of the IRS.
  • Nine states have no state income tax at all, so residents in those states file only a federal return to the IRS.
  • The IRS and state tax agencies do not share the same forms, important date, or filing systems, even though both may be due on the same date.
  • Some states use the federal tax code as a starting point but then add or subtract their own rules, which is why your federal and state tax bills can differ.

How federal and state taxes work separately

When you earn income, the federal government and your state government both want a cut — if your state has an income tax. The IRS collects the federal portion. Your state's tax agency (often called the Department of Revenue, Tax Commission, or similar) collects the state portion. These are two completely separate systems with different rules, different forms, and different important date.

Your employer withholds federal taxes from your paycheck and sends that money to the IRS. Your employer also withholds state taxes (if applicable) and sends that to your state. When you file, you report your income to both the IRS and your state separately. If you overpaid, the IRS refunds you federal money, and your state refunds you state money — these are two different checks or deposits.

The federal tax code is written by Congress. State tax codes are written by each state's legislature. A state can choose to follow the federal code closely, or it can write its own rules. Some states use federal taxable income as a starting point and then add back certain deductions. Others have completely different tax brackets and rates. This is why your federal tax bill and state tax bill are rarely the same amount.

Which states do not have income tax

Nine states do not collect state income tax at all: Alaska, Florida, Nevada, South Dakota, Tennessee, Texas, Washington, Wyoming, and New Hampshire (which taxes only dividends and interest income, not wages). If you live in one of these states, you file only a federal return to the IRS. You have no state income tax return to file.

Some of these states make up the lost revenue through sales tax, property tax, or other sources. But from an income tax standpoint, the IRS is your only income tax collector. If you move to one of these states, you stop filing a state income tax return, though you still file federal.

How to contact the IRS versus your state tax agency

If you have a question about your federal taxes or your federal return, you contact the IRS. The IRS has a phone line (1-800-829-1040), a website at irs.gov, and local IRS offices in many cities. The IRS also publishes forms like the 1040 (federal income tax return) and instructions that explore nationwide.

If you have a question about your state taxes or your state return, you contact your state's tax agency. Each state publishes its own forms and instructions. You can find your state tax agency by searching "[your state name] department of revenue" or "[your state name] tax commission." State tax agencies also have phone lines and websites, though wait times and response times vary by state.

Do not assume the IRS can answer questions about state taxes, and do not assume your state tax agency can answer questions about federal taxes. They are separate organizations with separate informed. If you are unsure which agency to contact, look at the form or notice you received — it will say "IRS" or your state's name at the top.

Why the IRS and state agencies sometimes coordinate

Even though the IRS and state tax agencies are separate, they do share some information. When you file your federal return with the IRS, the IRS may share your filing information with your state tax agency. This helps states verify that you filed and reported your income correctly. However, this information-sharing does not mean the IRS works for your state or that your state works for the IRS — they remain independent agencies.

Some tax software allows you to file both your federal and state returns in one place, which can make the process feel seamless. But behind the scenes, your federal return is being sent to the IRS and your state return is being sent to your state. The software is just a middleman handling both submissions.

What happens if you owe back taxes to the IRS

If you owe federal taxes to the IRS, that is a federal debt. The IRS can place a federal tax lien on your property, garnish your wages, or offset your federal refunds. These are federal enforcement actions. Your state cannot collect federal taxes for you, and the IRS cannot collect state taxes for you.

If you owe state taxes, your state tax agency handles collection. They can place a state tax lien, garnish your wages under state law, or offset your state refunds. Again, these are separate systems. You could owe the IRS money and owe your state money at the same time, and you would be dealing with two different agencies, two different payment plans, and two different collection processes.

Frequently Asked Questions

Can the IRS tell me how much state tax I owe?

No. The IRS calculates only federal tax. Your state tax agency calculates state tax based on your state's rules. The two are separate calculations. You need to file with your state tax agency or use state tax software to find out what you owe your state.

Do I have to file with both the IRS and my state?

You must file with the IRS if your federal income is above the threshold set by Congress that year. You must file with your state if your state has an income tax and your income is above your state's threshold. If your state has no income tax, you file only with the IRS. Check your state's tax agency website to confirm whether you must file a state return.

If I file my federal taxes late, do I have to file my state taxes late too?

No. Federal and state important date are usually the same (April 15), but they are set by different governments. If you file late with the IRS, you may owe federal penalties. If you file late with your state, you may owe state penalties. Filing late with one does not automatically mean you are late with the other — you must file both on time to avoid both penalties.

What if my state and the IRS disagree about how much I owe?

This can happen if your state interprets the tax code differently than the IRS does. You would handle the federal dispute with the IRS and the state dispute with your state tax agency separately. You may need to file an amended return with one or both agencies, or you may need to appeal to each one independently.

Is my state tax refund the same as my federal refund?

No. Your federal refund comes from the IRS and is based on federal taxes you overpaid. Your state refund comes from your state and is based on state taxes you overpaid. They are calculated separately and deposited separately. You could get a federal refund and owe state taxes, or vice versa.