If you've lived in the U.S. illegally but become eligible for a family-based green card, you have probably discovered a problem: When the date finally comes for your green card interview, you'll need to leave the U.S. for a U.S. consulate in your home country—but the consular officer might blocked your return based on your past time spent in the U.S. unlawfully. One solution to this trap is what's called a "provisional waiver" (or "stateside waiver") of the unlawful presence ground of inadmissibility.
(For a full discussion of the underlying problem, see Consequences of Unlawful Presence in the U.S.—Three- and Ten-Year Time Bars.)
By applying for a provisional waiver, you can get a "yes" or "no" answer from U.S. Citizenship and Immigration Services (USCIS) before departing the U.S. for the visa interview. With a "yes" answer, you can leave the U.S., feeling fairly comfortable that the consular officer will approve the immigrant visa and allow you to return to the U.S. with an immigrant visa, as a permanent resident.
If the answer from USCIS is "no," you will at least find out while still in the U.S., not trapped outside for three or ten years. You might even be able to reapply for the waiver. Or you can take a chance and leave the U.S. for a consular interview and present the waiver application there. This article discusses the scope of and limitations on eligibility.
When the provisional waiver first became available on March 4, 2013, applicants had to be immediate relatives of U.S. citizens—that is, a spouse, parent, or unmarried child under age 21.
In 2016, however, the waiver was greatly expanded. Now, anyone who is eligible for an immigrant visa (whether based on family, employment, the diversity visa lottery, or a special immigration classification) may apply for a provisional unlawful presence waiver.
The other eligibility requirements are that the applicant be:
The agency in charge of deciding on provisional stateside waiver applications is U.S. Citizenship and Immigration Services (USCIS), even if the applicant is in removal proceedings. Only applicants whose removal proceedings have been administratively closed and have not been recalendared, however, will be eligible to apply. After the USCIS approval of the waiver, they will need to obtain termination or dismissal of their cases by the immigration court before leaving the U.S. for their consular interview.
For guidance to the application process, see How to Apply for Provisional Waiver of Three- or Ten-Year Time Bar.