If you mistakenly filed a Form 1040 U.S. Individual Income Tax Return and you need to file Form 1040-NR U.S. Nonresident Alien Income Tax Return, or vice versa, you will need to amend your return. For steps on creating an amended return, see Form 1040-X - How to Create an Amended Return.

See the IRS Instructions for Form 1040-X and IRS Publication 519 for details

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