Pan traps (colored plastic bowls) are frequently used as an efficient standardized method of sampling bee faunas. We explored the utility of pan traps in three colors compared to net collecting using simultaneous sampling at biweekly intervals throughout the flowering season (May–Sep) at 11 sites in the eastern Great Basin Desert. Pan traps deployed for one day (9:00–16:00) on average captured significantly larger samples than net collections (2 hr.) at all intervals except the latter half of May. Average species richness for net collections exceeded pan traps only during late May and late September, periods with abundant floral resources. Capture rates were similar between colors. The composition of bees was also similar; Sørensen's similarity values exceeded 0.7. Color preferences for pollen specialists did not match flower color of their hosts. There were significant differences in species composition between net collections and pan trap collections. Almost one-third of the species showed a strong bias toward one method and in some cases between pan trap colors. The methods appear complementary: Halictinae and Perdita were predominantly collected in pan traps (85%); three genera, Anthidium, Colletes, Epeolus were largely or entirely detected by netting. Net collecting should be used in addition to pan traps if comprehensive inventories are desired. Though pan trapping constitutes a standardized method that avoids collector bias, it may not be unbiased; capture rates were lowest when flowering plant richness was greatest.