How long should Federal and State Income Tax Returns be kept?

As for the states I'm interested in Arizona & Texas.

Public Comments

1. 7 years
2. You can file a revised form for three years, so that is the minimum. In general, a seven year window for audits and whatnot are recommended.
3. 1) You owe additional tax and situations (2), (3), and (4), below, do not apply to you; keep records for 3 years. 2) You do not report income that you should report, and it is more than 25% of the gross income shown on your return; keep records for 6 years. 3) You file a fraudulent return; keep records indefinitely. 4) You do not file a return; keep records indefinitely. 5) You file a claim for credit or refund* after you file your return; keep records for 3 years from the date you filed your original return or 2 years from the date you paid the tax, whichever is later. 6) You file a claim for a loss from worthless securities or bad debt deduction; keep records for 7 years. 7) Keep all employment tax records for at least 4 years after the date that the tax becomes due or is paid, whichever is later. There are other questions that you need to ask/answer before you can pinpoint a time, but, in general, if you haven't done anything like 2 and 3 above, 7 years should be fine.
4. Seven years is the recommended time...however if the IRS discovers fraud in any year, they can go back as far as they want. As far as Texas is concerned....there is no state income tax.
5. 7 years should be fine. NN has a great answer.