When filing an application to sponsor a family member for a US green card, you will typically need to file some type of affidavit of support, generally either the I-864 Affidavit of Support or the I-134 Affidavit of Support. In a visa application, the affidavit of support plays an important role. It shows immigration officials that you are willing to support your family member once in the US, to ensure that your family does not rely on tax-funded public benefits in the US. In fact, by signing an affidavit of support, you are legally obligating yourself to take care of your family in the US while they pursue a green card.
Whether you need to file an I-864 Affidavit of Support or an I-134 Affidavit of Support will depend on the type of family green card application you are filing. You will generally need an I-864 Affidavit of Support if you are filing a visa application for a spouse and you will need an I-134 Affidavit of Support if you are filing for a fiancé(e) (k1 or K3 visa applicant). You will need an I-864 for most visa applications for immediate relatives and also for some employment-based immigration applications. The two types of Affidavit of Support differ in other ways as well. For example, the I-864 Affidavit of Support is legally binding. If you and your spouse are separated, you will still be financially responsible for your spouse, to ensure that they do not become a burden on the state. As well, you can co-sign on an I-134 Affidavit of Support if you need some additional income or assets declared on the petition to be accepted. In addition, Form I-134 is much simpler and smaller. The two-page application asks for some basic financial information while the I-864 Affidavit of Support is more involved and requires much more detailed information. As a result, the processing times for the I-864 Affidavit of Support can be longer.
Despite the differences, the I-864 Affidavit of Support and the I-134 Affidavit of Support are similar in many ways. Both are necessary for some green card sponsorship applications and both forms will ask you to make statements about your financial resources, including income and assets. Both the I-864 Affidavit of Support and the I-134 Affidavit of Support require that you show that you are sufficiently above federal poverty guidelines to support your family member in the US.