FAMILY BASED IMMIGRATION
US citizens who are 21 years of age or older can petition for immediate relatives to immigrate to the United States as permanent residents. Immediate relatives are limited to spouses, children under the age of 21, and parents. There is no limit on the number of immediate relatives who can immigrate to the United States every year. Individuals who immigrate get what are called "immigrant visas" or "green cards", also known as permanent residency.
VISA RETROGRESSION/WAITING LISTS
US citizens and permanent residents can also petition for some other relatives to immigrate to the United States, but the process is not nearly as fast as for immediate relatives. Some other relatives can immigrate through preference categories, described below:
First Preference (F1):
Unmarried Sons and Daughters of U.S. Citizens
--F2A: Spouses and Children of Permanent Residents
--F2B: Unmarried Sons and Daughters (21 years of age or older) of Permanent Residents
Third Preference (F3):
Married Sons and Daughters of U.S. Citizens
Fourth Preference (F4):
Brothers and Sisters of Adult U.S. Citizens
Under U.S. law, no more than 226,000 immigrant visas (i.e. green cards) can be granted in the family based preference categories in any one year period. The 226,000 immigrant visas are divided between the various preference categories (i.e. First Preference, Second Preference, Third Preference). In addition, within the overall allocation, there is also a per country limit. (For example, individuals born in Mexico and the Philippines have longer wait times than other countries because individuals from these countries apply for a disproportionate number of green cards across all of the preference categories).
Unfortunately, the demand for immigrant visas/green cards exceeds the supply, on a per-country basis, in a particular preference category and/or on a worldwide basis. When the demand for immigrant visas exceeds the supply, immigrant visas are not immediately available and a problem called “visa retrogression” occurs. In periods of visa retrogression, even when there is an approved I-130 petition for a family member, the individual essentially has to wait “in line” for his or her turn to file the last step of the permanent residency case, known as the I-485, or, if the family member is outside of the US, they will have to wait “in line” to apply for the green card at the US consulate abroad. An individual’s place in line is determined by the priority date. The priority date is the date the I-130 petition is filed.
To find out how many years the petition would take to process before the relative can immigrate to the United States, you have to check the Visa Bulletin, which is published every month by the State Department at: https://travel.state.gov/content/visas/en/law-and-policy/bulletin.html
The Visa Bulletin is typically published mid-month, showing availability for the following month. Please note that if a certain preference category is retrogressed by 10 years, it may not be exactly 10 years before the individual can process the green card; rather, it’s necessary to follow the Visa Bulletin over several months to get a better prediction of how quickly dates are moving forward and how soon an immigrant visa might be available.