The IRS recommends
taxpayers keep their returns and any supporting documentation for 3
years after the date of filing; after that, the statute of limitations
for an IRS audit expires.
If you've under-reported
income by 25 percent
, however, the IRS can
go 6 years back, or 7, if you claim a loss
for bad debt or worthless securities.
If you don't file, or
if you file a fraudulent return, the IRS has no statute of limitations; so it may be best to keep your records
indefinitely.
State documentation
requirements
If you're paying state income
taxes, the time you need to keep records will vary, depending on
the particular state's laws.
Please see the
following TurboTax guide, "How Long Do Federal and State Tax Returns Need
to Be Kept?":
https://turbotax.intuit.com/tax-tools/tax-tips/General-Tax-Tips/How-Long-Do-Federal-and-State-Tax-Re...
