INTRODUCTION In honeybee breeding schemes, the generation interval is often two years on the dam path. This allows phenotyping of certain traits, such as honey yield, during a full beekeeping season to measure early to late-season harvests. Other traits, however, such as hygienic behavior (HYG), can be phenotyped early, within the first year of birth of queens. Using simulation, we investigated the impact of reducing the dam’s generation interval from two to one year on the genetic gain and inbreeding build-up, after 20 years of selection. METHODS We simulated populations under selection, with individual queens, worker groups, and drones, using an polygenic model adapted to bee specificities. We simulated two breeding schemes. In the ‘base’ scheme, the dam and sire generation interval were both two years, allowing the phenotyping of honey yield in addition to HYG on both potential dams (breeding queens, BQs) and potential sires (drone-producing queens, DPQs). In contrast, in the alternative scheme, the dam generation interval was reduced to one year, allowing for the phenotyping of only HYG on BQs, while the sire generation interval remained two years with complete phenotyping of DPQs. A yearly winter mortality randomly eliminated 25% of all BQs and all DPQs. The genetic correlation between honey yield and HYG was either 0, -0.6, or +0.6. The breeding goal was the sum of breeding values of honey yield and HYG with the same weights. RESULTS In all scenarios, the alternative scheme outperformed the base scheme, yielding 40 to 45% greater genetic gain. However, this additional genetic gain was accompanied by an increase in inbreeding of 20% to 35%. CONCLUSION Reducing the generation interval proved to be a powerful way of increasing genetic gain even though it meant that honey yield could not be phenotyped on potential BQs. However, it also brought more inbreeding.