The movie was inspired by the story of Mehran Karimi Nasseri. He landed at Charles De Gaulle Airport near Paris in 1988, after being denied entry into England because his Iranian passport and United Nations refugee certificate had been stolen. French authorities wouldn't let him leave the airport, so he remained in Terminal One, a stateless person with nowhere else to go. He was eventually granted permission to either enter France or return to Iran, but he chose to live in the terminal and tell his story to anyone who would listen. Reportedly, his mental health deteriorated over the years. When given the opportunity to live in France, he refused because the documents did not identify him as "Sir Alfred", and he claimed to have forgotten his native Persian. He left the terminal in August 2006 to be hospitalized for an unspecified illness. Afterward, he lived in a hotel on the money received from the film (DreamWorks reportedly paid him $250,000 for the use of his biography). Nasseri moved back to Charles de Gaulle airport in October 2022. He died in terminal 2F on November 12, 2022.
The airport set built for the film was based on Düsseldorf International Airport. The set was a near-full-size replica built in a former hangar, with three working sets of escalators, and populated by many popular stores (e.g. Burger King, Mrs. Fields, W.H. Smith). Some of these brands were recruited by DreamWorks, while others approached the studio when word of the production got out. Many of the stores and restaurants were built by the construction crews that built the actual mall and airport stores for the respective companies, and some had fully-functioning equipment, such as ovens and cash registers. However, the inclusion of a brand on the set was not a guarantee of inclusion in the film; DreamWorks retained full control over editing, and some brands appear only briefly or not at all.
Originally, Viktor was going to arrive from Slovenia. It was changed after the advice from Mark Rijavec, the former consul of Republic of Slovenia in the United States. Some people consider Slovenia to be the Switzerland of the Eastern Europe, and he said it wouldn't look credible if a civil war were to start in one of the new members of the European Union.
In a deleted scene, Navorski gets help using a phone card and says, "Home phone, home phone!" Steven Spielberg cut it because he didn't want comparisons to E.T.: O Extraterrestre (1982) and the famous lines "Phone home."
The note on the photocopy of the hand attached to the sign "All Gates" says "FREE THE GOAT."
Sasha Spielberg: The girl with the suitcase that Viktor tries to help is Steven Spielberg's daughter.