Go to this IRS website for information on how long to keep certain records and tax returns - https://www.irs.gov/businesses/small-businesses-self-employed/how-long-should-i-keep-records
Go to this IRS website for information on how long to keep certain records and tax returns - https://www.irs.gov/businesses/small-businesses-self-employed/how-long-should-i-keep-records
Some states have longer Statutes of Limitations than Federal does.
I always recommend keeping paper copies of tax returns forever - let your heirs dispose of them. You never know when information from years ago might be needed to prove something. Computers and programs come and go over the years so no telling what electronic file from today can be read 50 years from now, but paper can always be read. (Just recently a 1945 tax return for the aunt of a taxpayer that died years ago helped win a court case involving property title - the Aunt keep everything ).
If you believe CDs will last forever, and not be lost in fire or flood, and have read drives available for them, then you can start shredding. Most laptops don't have CD drives even now.
The electronic copies must be the PDF copies too...the .taxyyyy datafiles will be totally useless to you in ~1 years, the PDF files may last longer...but no promises as we don't know where things are headed.
USB flash drives in the bank safety deposit boxes will work....and when a new memory device shows up in a few years, you can copy the files to the new memory device to keep them current.
Paper does last better, as long as it is not in a home that burns down, or gets hit by a hurricane or flood. But even in a bank safe deposit box, a few zip-locks are a good idea (My mom's stuff was in one at a bank that was flooded...all the boxes filled up with water and sediment)
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