Removal is the process of removing immigrants from the United States that are found either inadmissible or deportable. Individuals are removed from the United States, due to a specific reason. If one is determined to be inadmissible or deportable, it is related to the reason for why one is removed. These terms do not mean the same.

A deportable alien can be defined as any person who entered the United States illegally. However, a person who entered legally but breached the terms of their classification or visa (e.g. overstayed a valid visa) is also considered a deportable alien. Deportability is related to a person already in the United States. Being inadmissible is only related to individuals trying to enter the United States at a border crossing such as an airport, land, or sea border.

A person considered inadmissible does not qualify to enter the United States according to the USCIS. There can be several reasons why one can be determined to be inadmissible, including a prior conviction of certain crimes, immigration fraud, or simply failing to comply with the terms of one's visa. There are many more reasons one could be determined as inadmissible. However, United States citizens would rarely be denied entry into the country. An individual being inadmissible has two choices:

1. Be removed
2. Ask to withdraw the application for admission to the United States

Being removed or withdrawing an application can result in different implications. For example, if you enter the United States but are being detained, you can ask to voluntarily withdraw your application to enter.