If you have not yet filed, you will add the new W-2 by logging into Turbo Tax, selecting Federal Taxes then Wages & Income, scroll down to W2 and add.

If you have already filed, you will have to do an amendment to enter the information from that W2.  It cannot be entered in your 2016 return.  Please see the one page article from the IRS on Tips For Filing An Amended Return.  This should help to guide you on whether or not you should file an amendment based on the changes on the W2, not all changes require an amendment.  If you do have to file an amendment, please see the link below to get the process started.  However,  don't worry you generally have 3 years to amend your taxes, unless you will owe, then it would be best to do it as soon as possible after receiving your refund, to avoid penalties and interest.  I would recommend that you wait until after receiving your refund before working on your amendment as this could delay the process.

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