The newspaper Paris-Midi of February 24, 1939, makes mention of the artist: "Tamara de Lempicka bids good-bye to Paris, where she yesterday boarded the SS Paris headed for New York."
Once in New York, she put on two shows, a first one at the Paul Reinhardt Gallery in May 1939, and a second at the Julian Levy Gallery in 1941.
September 1941 found her off to California, to San Francisco and then on to Los Angeles, the cities to which Julian Levy had made her show travel. At that point, she and her husband decided to rent King Vidor's residence in Beverly Hills (Los Angeles), where they stayed until 1942, the year they returned to New York. The couple also took possession of a country house in Westport, Connecticut.
At the war's end, Lempicka frequently "commuted" between Italy, France (where she had kept her rue Méchain studio), and the United States, not to mention numerous side trips to Cuba and Mexico.

The Kuffners decided to live in Hollywood, buying a house belonging to the film director King Vidor. De Lempicka threw herself into charitable work in support of wartime in Europe, and was given the rank of Staff Sergeant in the Women's Emergency Corps (whose uniforms she had designed). She requested American citizenship.