My nephew is a US citizen and is going to college at this time. He has filed an immigrant visa petition for his foreign national spouse (who lives overseas) and is now at a stage where an Affidavit of support (form I-864) is to be filed. He is jobless and has had little income from part time jobs during the past three years so it does not look like he can file I-864. I am willing to provide an Affidavit of Support but the form I-864 seems to be for the petitioner or potential employer only. I can submit an I-864A but only if he can submit an I-864 which he does not seem qualified to do.

Is there an option for me to use a different Affidavit of Support form (like I-134)? If not, what other options may be available?

Thank you.

If you do not live in the same household: As a joint sponsor you also need to fill out the I-864. You would check Box d under question 1. As the primary sponsor your nephew will have to submit an I-864 as well.

If he lives in your household: then he would fill out the I-864 and you would fill the I-864A.

Thanks for the info. The petitioner does not live in my household. Does this mean that both of us have to fill our own I-864's?

Indeed. Your nephew has to submit his own form, since he is the primary sponsor (even if he has no income). You will submit another I-864.
Good luck!

Yes, exactly.

Yes. Each one file an I864. If he doesn't have a job for now, instead the employment letter, he can attach an explanation letter where he says the reason because of he was unemployed last years and for now (ex. school). Also, the petitioner must attach his own employment letter and the last 3 yrs. of income tax return.
Good luck.