What is Fourth Preference?
Fourth Preference meaning A category of family immigration (F4) for brothers and sisters of U.S. citizens and their spouses and children. The U.S. citizen must be 21 years of age or older before he/she can file a petition under this category. Before 1992, this was known as fifth preference (P-5). Visit our Family Based Immigration webpage for more info.
reference: U.S. Visas – Glossary