If you have been granted an immigrant visa by a U.S. embassy or consulate, you are almost a permanent resident of the United States (green card holder)—but not quite. The last step in your process is to travel to the U.S. and pass inspection at the airport, docking point, or land border. You must enter the U.S. before the expiration date on your visa. If you are immigrating in a family group, the principal applicant must enter the U.S before or at the same time as the rest of the family.
When your visa was issued, you will also have received a sealed packet containing your immigration file. Do not open this packet. You should hand carry the packet with you and not put it in your checked luggage.
You should also hand-carry your X-rays from your medical exam if they were given to you, as the X-rays do not fit in the packet. (In the near future, after late 2019, this process might change, and all immigrant visa file documents will be transmitted electronically, eliminating the need for the paper packet.)
If you are arriving in the U.S. by plane, upon exiting you should enter the line for "Permanent Residents," unless there is a specific line designated for new permanent residents.
The first U.S. Customs and Border Protection (CBP) officer you meet will verify your identity, then direct you to a designated secondary inspection area for new immigrants. This inspection normally takes place at the first U.S. airport at which you land, even if your ultimate destination is somewhere else. Or, depending upon where you are coming from, you might instead go through "pre-flight-inspection," in which a U.S. immigration officer inspects you at the airport you depart from.
If you are entering at a land border, the primary inspection officer will direct you to a parking area. You will then go inside the office at the bridge for further inspection. Procedures can vary depending on location, so as you approach the U.S. border, be aware of signage that might direct you to a designated line or pre-border parking area for new immigrants.
In the secondary inspection area, whether at an airport or land border, the officer will open your packet and review your documents. Immigrants with certain medical conditions might be given information about where to go for a follow-up medical exam in their new town of residence.
The majority of people entering on immigrant visas are admitted to the United States with little or no difficulty. Still, this process can take time, sometimes hours, so allow plenty of time between connecting flights.
In some locations, there might be other people in the secondary inspection area who were referred there because of immigration violations or criminal convictions. You might see people being questioned and denied entry, but this is no cause for concern. Secondary inspection areas are used for anyone whose processing may take longer. If you had a previous immigration violation or criminal conviction, the officer will verify that you obtained the proper waiver or that the consular officer was aware of the information and determined you were still eligible for the visa.
If all goes well, your passport will be stamped to show your status as a lawful permanent resident (or lawful conditional resident if you're immigrating based on a marriage that is less than two years old).
Your actual green card will be mailed to you some weeks later.