Western cherry fruit fly, Rhagoletis indifferens Curran 1932 (Diptera: Tephritidae), was reared from naturally-infested Chinese crabapple, Malus spectabilis (Aiton) Borkhausen (Rosaceae), in Washington State, U.S.A. Pupae from Chinese crabapple were smaller than those from sweet cherry, Prunus avium (Linnaeus) Linnaeus (Rosaceae), but fecundity and longevity of flies from the two hosts did not differ. Laboratory experiments were conducted to compare larval development in crabapples and cherries. ‘Snowdrift’ crabapples (Malus × ‘Snowdrift’) did not produce pupae. Percentages of ‘Indian Magic’(Malus ‘Indian Magic’) ‘Radiant’ crabapple (Malus ‘Radiant’) vs. sweet cherry replicates that produced pupae did not differ in two no-choice experiments (36.7 vs. 41.7% and 13.3 vs. 33.5%, respectively). In a choice experiment, the percentage of crabapple replicates that produced pupae (6.7%) was lower than that of cherry replicates (42.2%). Egg to pupal development times in crabapples (18.0–21.2 d) were longer than in cherries (15.4–16.7 d) and pupae from the crabapples were smaller. Results suggest crabapples are not optimal developmental hosts for R. indifferens but that Chinese and ‘Indian Magic’ ‘Radiant’ crabapples can occasionally allow late-season flies to bridge the gap between one generation and the next when no cherries are available.