We determined the distribution of Rhagoletis fausta (Osten Sacken 1877) and Rhagoletis indifferens Curren 1932 (Diptera: Tephritidae) in California outside the state interior quarantine area. Our data confirmed the historical records of R. fausta in Alpine, Amador, El Dorado, Fresno, Kern, Mariposa, Mendocino, Modoc, Mono, Nevada, Placer, Plumas, Sierra, Tehama, Tulare, and Tuolumne counties and we trapped R. fausta for the first time in Butte, Calavaras, Glenn, Inyo, Lassen, Madera, and Yuba counties. We confirmed the historical records of R. indifferens in Amador, El Dorado, Fresno, Mendocino, Modoc, Nevada, Placer, Plumas, and Sierra counties and we trapped R. indifferens for the first time in Butte, Calaveras, Lassen, Madera, Mariposa, Tulare, Tuolumne, and Yuba counties. No R. fausta were trapped in Lake, Los Angeles, or San Bernardino counties and no R. indifferens were trapped in Alpine, Glenn, Inyo, Lake, Mono, or Tehama counties. The lower altitude at which we trapped both flies increased significantly southward from the northern end of the flies' range in California. The large, host free distances between the populations of R. fausta and R. indifferens and the major commercial sweet cherry production areas in California and the asynchrony between the time when commercial sweet cherry fruit are available for attack and the presence of adults of both fly species effectively prevent the adult flies from naturally dispersing into the major commercial sweet cherry production areas of the state and establishing breeding populations.