You generally file your taxes with the federal government (IRS) and, if applicable, your state or local tax agency, usually online through approved e‑file systems or by mail to the correct address for your location and form type.

Federal tax: where to file

For U.S. federal income tax, you file your Form 1040 with the Internal Revenue Service, either:

  • Electronically (recommended) through IRS e‑file, commercial tax software (e.g., TurboTax, H&R Block, etc.), or a tax professional’s e‑file system.
  • On paper by mail to an IRS processing center; the specific mailing address depends on your state, whether you include a payment, and the exact form (1040, 1040‑X, etc.).

The IRS maintains a “Where to File” page that lists the mailing addresses by state and form type, which you must follow closely if you choose paper filing.

State and local taxes

In addition to federal filing, many people must also file with a state and sometimes city or local tax agency.

  • Most states offer online portals to e‑file or pay, and many also accept e‑filed state returns submitted together with your federal return via tax software.
  • Deadlines and addresses for state returns vary; you need to check your state’s revenue or taxation department website for exact “where to file” instructions.

Ways you can file

You can usually choose among several filing methods for both federal and state taxes.

  • Tax software / online services : Step‑by‑step interview style, then e‑file for you.
  • Tax professional : An enrolled agent, CPA, or preparer files electronically on your behalf.
  • Paper forms : Download, print, complete by hand or on a computer, then mail to the correct address listed for your location and situation.

If you tell more about your country or state, it’s possible to narrow down the exact site and address you should use.