Each form are used to demonstrate that the beneficiary of the petition. The
Form I-134 is a 2 page simple document which gives basic financial information and its not legally binding. The
Affidavit of support Form I-134 is used in certain non-immigrant cases. But even K-1 and K-3 will use Form I-134 even thought the beneficiary applied to reside in United States.
The
Form I-864 is for all the family-based immigrants, for both immediate relatives or preference categories or employed immigrants. The Form I-864 is very detailed when compared with Form I-134, it require detailed financial information, and is legally binding.