@bhbaothebeginning
1) If you have not actually filed your original tax return yet
IF you already entered your W-2 into the software, you edit that one and change just the boxes that changed as shown on the W-2C...leaving whatever boxes already filled in as-is. Then on a page following the main form, there is a checkbox to indicate that it represents a W-2C
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IF you have not entered the original W-2, you enter all the boxes for that one....but change just the boxes that show as being changed from the W-2C. Then on a page following the main form, there is a checkbox to indicate that it represents a W-2C
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BUT
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2) IF you have fully-filed your original tax return already. You might have to amend it. But, that depends on what the employer actually changed. Some changes are immaterial to your tax filing and don't require an amendment, so you'd have to tell us what box $$ and/or codes changed for the W-2 C...AND, what tax year the W-2C is for (Some 2020 W-2C's have been coming out that don't require amendments)
____________*Answers are correct to the best of my knowledge when posted, but should not be considered to be legal or official tax advice.*
