Steps After Immigrant Visa Interview
Immigrant visas are valid for 6 months after the interview date. You must enter the U.S. within that duration. An immigrant visa is a single entry visa. You become a permanent resident only when you enter the U.S. Until then, you just have an immigrant visa and you don't have any particular status in the U.S. just because you have an immigrant visa.

A visa is not a guarantee of entry into the U.S. The visa simply allows you to travel up to the U.S. port of entry (usually airport). Regardless of your final destination, port of entry is the first location in the U.S. where your plane lands.

The principal applicant must enter before or at the same time as any of the derivative beneficiaries. After that, the remaining family members may enter at any time in any order within the validity of the immigrant visa.

Tips on airlines and travel agents

If you are unable to enter the U.S. within the validity of the immigrant visa, you may make a written application to the U.S. consulate to increase the duration. However, unless you have a proper application that justifies the unavoidable circumstances beyond your control, your application will not be honored.

Enter the U.S. as an Immigrant
You don't fill I-94 form in the flight, just the customs form. You enter the U.S. with your immigrant visa, passport, your medical X-ray report, the sealed envelope provided by the consulate after the immigrant visa interview. At the port of entry, you will be taken to a special room (or there may be a separate section for new immigrants, depending upon the airport) and the immigrant visa in your passport will be printed with an I-551 stamp which is a temporary green card, valid for one year. It indicates the date and port of entry for admission as a lawful permanent resident of the United States. You will get the actual plastic green card (which looks just like a driver's license in the U.S.) in the mail within few months. At port-of-entry, you will also be fingerprinted which just takes a couple of minutes. When asked to sign, remember to sign in black pen. If you are in EB3, for example, your passport will be stamped with E31, your spouse E34 and your children E35. Similar numbers for other categories. A temporary green card is as good as permanent green card except that it expires in one year.

Depending upon the volume of traffic at the port of entry on that day, the above process may take several hours. Therefore, if the port of entry is not your final destination, make sure to book your air tickets with a sufficient gap for your domestic flight.

If you were in the U.S. previously and had had already applied for I-485, the A# number in your I551 stamp should be from the immigrant visa, and not from I-485/EAD. In the actual plastic green card, the A# number will be from immigrant visa.

If the immigration officer detects anything wrong in your documents or with your answers to his/her questions, he/she can use expedited removal powers to send you back home and bar you from entering the U.S. for 5 years.

Marriage Based Immigration
If your marriage will be less than 2 years old when you enter the U.S. as new immigrant, you will be admitted into the U.S. as conditional resident and not permanent residence. Ninetey days before the 2-year anniversary, you will have to apply to remove the conditions to get permanent residence. Therefore, if your 2-year anniversary is close (before 6-month immigrant visa expires), wait until after your 2-year anniversary to enter the U.S. to receive permanent residency directly. Make sure to point to the immigration officer at the port of entry so that he/she stamps your passport for permanent, not conditional, residence.

Immunization and Medical Records
When the child is first enrolled into school, every state in the U.S. requires that children have complete immunization records. In most states, this also applies to transfer students entering any grade. Therefore, you are strongly recommended to carry complete immunization records and your medical records of prior disease or treatment. Prior to departure to the U.S. they should be obtained from their private physicians, hospitals, local health departments, or schools.

Post Entry
Welcome to United States as a permanent resident.

Newcomer's guide to USA

Plastic Green Card
Your plastic green card would arrive in your mail by normal U.S. mail within 2-3 months. It would come from the USCIS service center. On the envelope, some USCIS service centers write do not forward. So if you change your address between the time you enter as an immigrant and you would hopefully get the plastic card, you should promptly file Change of Address Form (Form AR-11) to USCIS and follow up with them to make sure that they have your current mailing address.

Sample USCIS envelope containing permanent resident card

Work Authorization
Before getting an immigrant visa, if you had been working in the U.S., you would normally have a non-immigrant visa such as H1B, L1 etc (some of you might even be working on EAD if you are on H4, L2 etc.), those non-immigrant visas would have got cancelled at the time of consular interview. So they are no longer valid to work. So you should ask your employer to give you an I-9 form (Employment Eligibility Verification Form) and you should fill it. Give them the copy of your I-551 stamp in your passport. Now you can legally work with your employer based on your green card.

Social Security Card
When the person is on a non-immigrant visa, he/she would have either a social security card with "Valid to Work with USCIS Authorization only", or "Not Valid to Work" or no social security card at all. You should go to the nearest Social Security Administration office and get a new Social Security Card. You can fill out the fillable form SS-5 and print before you go there. You will get a new Social Security Card with those restrictions removed. You will retain the same old Social Security Number, though.