U.S. Family Immigration 

This visa allows fiancé of a United States citizen to immigrate to the United States while their green card is processing.

The fiancé visa first requires that the United States citizen and their foreign fiancé have the intention to marry and they must agree to do so within ninety days of the foreign fiancé entering the United States There is also a requirement that they have physically met within two years of filing the application and as with any family sponsorship it is important to document the genuine and bona fide nature of the relationship through photographs, affidavits from friends and family, as well as all evidence of correspondence.

Family green card applications to the United States are roughly divided into two main categories: 1) Immediate relatives and 2) Preference Categories. 

Immediate Relatives Category:

Starting with immediate relatives such as spouses of United States citizens, children (unmarried 21 and under of United States citizens), and parents of United States citizens. Applications in this immediate relative category are processed the fastest and generally within one or two years.

Preference Category: 

First preference: Unmarried, adult sons and daughters of U.S. citizens (adult means 21 or older.)

Second Preference (2A): spouses of green card holders, unmarried children of permanent residents

Second Preference (2B): Unmarried adult sons and daughters of permanent residents

Third Preference: Married sons and daughters (any age) of U.S. citizens

Fourth Preference: Brothers and sisters of adult U.S. citizens.

There is a two-step process in family based cases.

First, the U.S. sponsor files an immigrant relative petition called an I-130 with USCIC.

Secondly, after the petition is approved and the priority date becomes current, the foreign relative can apply to a U.S. consulate abroad for an immigrant visa.

If the foreign relative is already in the U.S. in a legal status, the relative can file an I-485 to adjust status to that of a permanent resident, without leaving the United States. In the case of an immediate relative in the U.S., both the I-130 and the I-485 can be filed at the same time. After processing, the case is usually referred to a USCIS  local office for an interview.