My Husband is now a U.S. Resident, we want to file jointly and need advice!

Assuming you are a US Citizen or Green Card holder, and he has a SSN, (if he has an ITIN he should now get an SSN) I see no reason why you could not file jointly.

Forms? Form 1040 should work just fine.

Try

Election to File Joint Return

If, at the end of your tax year, you are married and one spouse is a U.S. citizen or a resident alien and the other is a nonresident alien, you can choose to treat the nonresident as a U.S. resident. This includes situations in which one of you is a nonresident alien at the beginning of the tax year, but a resident alien at the end of the year, and the other is a nonresident alien at the end of the year.

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How To Make The Choice

Attach a statement, signed by both spouses, to your joint return for the first tax year for which the choice applies. It should contain the following:

• A declaration that one spouse was a nonresident alien and the other spouse a U.S. citizen or resident alien on the last day of your tax year, and that you choose to be treated as US residents for the entire tax year, and
• The name, address, and social security number (or individual taxpayer identification number) of each spouse. (If one spouse died, include the name and address of the person making the choice for the deceased spouse.)

You generally make this choice when you file your joint return. However, you can also make the choice by filing a joint amended return on Form 1040X, Amended U.S. Individual Income Tax Return (PDF). 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 for which you made the choice.

You generally must file the amended joint return within 3 years from the date you filed your original US income tax return or 2 years from the date you paid your income tax for that year, whichever is later. Suspending The Choice

The choice to be treated as a resident alien does not apply to any later tax year if neither of you is a US citizen or resident alien at any time during the later tax year.