Family based permanent residency is accomplished through sponsorship by a U.S. permanent resident or citizen. These visas are available in two categories:
(1) Immediate relatives and (2) Preference immigrants. There is no limit on the number of people acquiring family based permanent residency through immediate relatives. However, preference immigrants are subject to yearly numerical limitations.

Immediate relatives are defined as one of the following:

(1) Spouses of U.S. citizens,
(2) Children (under 21 years of age) of U.S. citizens
(3) Parents of U.S. citizens ages 21 years or older
(4) Spouses of deceased U.S. citizens who were married at least 2 years at the time of spouse's death

Preference immigrants are divided into several categories:

First Preference Category:

(1) Unmarried sons or daughters (21 years of age and older) of U.S. citizens

Second Preference Category:

(1) Spouses and children (under 21 years of age) of lawful U.S. permanent residents
(2) Unmarried sons and daughters (21 years of age and over) of lawful U.S. permanent residents

Third Preference Category:

(1) Married sons or daughters (21 years of age and older) of U.S. citizens and their spouses and children

Fourth Preference Category:

(1) Brothers and sisters (and their spouses and children) of U.S. citizens aged 21 years and older

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