How long is the validity of American immigrant visa?

"American visa validity period" usually means that the American visa is valid and can be used for the same purpose during the period from the date of issuance to the date of expiration. To determine how many times you can go to the United States with this American visa, please check the number of entries on the American visa ("entry" means the number of entries). If the number of entries is multiple ("M" stands for multiple entries), then the owner of an American visa can travel to the United States for multiple times with an American visa before the expiration date, but the purpose of each trip must be the same. If you enter the United States once, you can only enter the United States once with an American visa within the validity period of the American visa.

The number of visa entry times in the United States can be any number, at least once and at most "m" (representing unlimited or multiple times), but the purpose of each entry must be the same. If you need to travel to the United States frequently and hold multiple entry tourist visas, you don't need to apply for a new tourist visa before going to the United States every time. However, it should be noted that although you have a multiple-entry tourist visa to the United States, you cannot use this American visa to work or study in the United States after entering the country.

The validity period of American visa means that during this period, you are allowed to show your American visa to the American immigration inspector at the entry port of the United States and ask to enter the United States. Holding an American visa does not guarantee that you will be allowed to enter the United States. You shouldn't confuse the validity of American visa with the time allowed to stay in the United States. The length of stay of American visa owners in the United States is determined by the immigration inspector at the entry port of the United States, and it is shown on your entry and exit record form (I-94 form or I-94W form issued to citizens of visa-free countries). The expiration date of American visa has nothing to do with the time allowed to stay in the United States every time you enter the country.

Certain circumstances may invalidate your valid US visa. If you do not leave the United States before the last stay date approved by the immigration inspector of the US Department of Homeland Security or the US Citizenship and Immigration Service (USCIS), your action will automatically invalidate your US visa. However, if you have submitted an application for extension of residence or change of identity in the United States in time, and the application is serious and reasonable, and you have never worked illegally in the United States, your American visa will usually not automatically expire. If you have submitted an application for changing your status and are waiting to become a permanent foreign resident of the United States ("green card" holder), you should contact the US Citizenship and Immigration Office in advance to apply for a departure permit ("re-entry permit").