Adopting an Integrated Pest and Pollinator Management strategy requires an evaluation of pesticide risk for pollinator species. For non-Apid species, however, the standardized ingestion assays are difficult to implement. This hinders the consideration of non-Apid species in farm management strategies and government regulatory processes. We describe a new method for a mason bee, Osmia cornifrons, which is an important pollinator of apples and other fruit crops. Our approach overcomes high control mortality seen in other bioassay protocols and expands testing to include males as well as females. The new pesticide toxicity assessment protocol showed that (1) a group feeding method is optimum even though there is no trophallaxis, (2) males had better tolerance to pesticides although they are smaller, and (3) pesticides can cause additional mortality after the standard 48 h assessment time specified by European Food Safety Authority and U.S. Environmental Protection Agency.