The full English name of the United States is United States of America.

US and USA are both the English abbreviations of the United States. US is the abbreviation of United States, directly translated as "United States". USA is the abbreviation of the full name of the United States of America, but its application is far less widespread than that of the US.

USA is most commonly used in sports events. Almost all international sports event management agencies, including the International Olympic Committee, have strict regulations that national abbreviations must use ISO standards.