What is form8949 and why do I need to mail it

[LindaA]

Form 8949 shows the details of your capital asset (investment) sales and exchanges. Sometimes it is necessary to mail the form to the IRS even if you file your tax return electronically. The FAQ below provides details.

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[pr-hudson]

Form 8949 is required to report capital gains and losses.  You will need to mail it if each investment is not listed individually or any category is unusual.