The United Federation (sometimes shortened to United Fed.) is a country to the west of Arstotzka. It is one of the four countries that do not border Arstotzka on the game map. Entrants from the United Federation are identified by a blue passport with a silver emblem on the front.
As with the other countries, not much background information is given in the game. An ex-inspector on day 18 explains that they used to deny most entrants when they worked at the border in the United Federation, and that the country now uses computers for processing entrants. The game does not provide enough information to compare the statement to the level of technology in other countries.
An Arstotzkan serial child killer, Simon Wens, escapes from a United Federation prison and comes to the border on day 30.