Amended past years returns

[a1aaron80]

I am a US citizen and have been married to a foreign spouse since 2018.  I found out in January of this year that I could include her on my taxes and file as MARRIED FILING JOINTLY.   I included her income on our tax return as well.  This is my first year to apply for her to get an ITIN.   Can I amend my tax filings from the last 3 previous years once I receive my Her ITIN ?  I've filed married filing separately before , I never knew of the huge tax break.  I have her pay statements for the last 3 years as well.

[AmyC]

It depends. 

If you haven't filed yet - You can amend returns up to 3 years to make the choice.

See Nonresident Alien Spouse | Internal Revenue Service which states:  

Once made, it applies to all later years.

If you make the choice with an amended return, you and your spouse must also amend any returns that you may have filed after the year 

If you have filed - It does not say that you can file amended returns after making the decision to create an earlier start date. You may be successful; but, nothing is definitive. It doesn't hurt to try.