If a foreigner is denied entry into the United States and deemed inadmissible by U.S. immigration authorities, it is generally the responsibility of the individual to arrange and cover the costs of their return flight home. In most cases, airlines will not allow a passenger who has been denied entry to board a return flight to the United States without proper documentation or authorization.

It is important for travelers to ensure they have the necessary visas or travel authorizations before attempting to enter the United States. If a person is denied entry, they may be detained by immigration authorities until they can make arrangements to leave the country.

In certain circumstances, such as if the denial of entry was due to an airline’s error or if the person qualifies for certain protections under international agreements, the airline may assume the responsibility for the return flight. However, this would typically be assessed on a case-by-case basis, and it is advisable for individuals to consult with the relevant authorities, such as the U.S. embassy or consulate, for guidance and assistance in such situations.

It is always essential for travelers to understand the entry requirements and have the necessary documents before embarking on international travel to any country, including the United States, to avoid complications or denial of entry.