You'll need to file an amended return to add the Form 1095-A. Wait until you receive your original refund before mailing your amended return to the IRS (it cannot be e-filed). The amended return (Form 1040X) will be available in mid-February. The FAQ below has more information, including an IRS video that discusses amended returns.
Note: If you receive a Form 1095-B or Form 1095-C after filing your tax return you do not need to file an amendment. Just store the form with your records.
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