Green cards are identification documents issued to legal permanent residents by the U.S. Citizenship and Immigration Services (USCIS). These cards are issued as proof of a foreign national’s legal status in the U.S.
The front side of the green card has biographic information about the card holder like the surname, given name, date of birth, sex and the country of birth. USCIS number also known as the Alien Registration Number and the green card expiration date are also printed on the front side of the green card.
The category number is printed next to the USCIS # on the front side of the green card below the word “Category.” Many are unaware of what the category on the green card mean. Category is the immigrant visa category through which a foreign national was granted admission into the U.S. as a legal permanent resident or as a conditional permanent resident.
USCIS refers to the category as “class of admission” in other official documents. The category code is usually one or two letters followed by a number.
The back of the green card has the stripe that the USCIS and other government agencies use to swipe and gather necessary information about the card holder.
Examples of Category codes:
Category codes for different categories of immigrants are different. That is because there are different ways to immigrate to the U.S. Some come here through family preference categories and some based on employment and some through the other different ways.
If your card has C21 below the word category, this means you have been granted entry into the U.S. as a conditional legal permanent resident as a husband or wife of a lawful permanent resident.
If you are an unmarried son or daughter of a U.S. citizen, your category code will be F11.
If you received your green card through the Diversity Visa lottery program, your category code will be DV1 or DV6.
The category codes can be found here. This page lists all valid category codes also known as Class of Admission codes.