@gems77
See page 2 here: https://dor.mo.gov/forms/MO-1040%20Instructions_2020.pdf
The PO box 3222 address is used for any MO tax returns with a refund (either amended or original) IF....if the paper tax return has a 2-d bar code. Since TTX prints the forms with the 2D barcode, that's where you send it.
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Folks who manually prepare their tax forms on paper and not using software...they won't have the bar codes and would use the other PO boxes.
____________*Answers are correct to the best of my knowledge when posted, but should not be considered to be legal or official tax advice.*
