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Butterfly abundance and diversity continue to decline with habitat fragmentation, degradation, and loss. Since butterflies play an important role in pollination, maintain overall grassland biodiversity, and act as biological indicators, research in butterfly ecology is imperative to gain insights into how land cover and context affect butterfly diversity and abundance. Currently, most butterfly research in the Northern Great Plains is restricted to monitoring surveys that do not account for imperfect detection. Our objective is to determine density or occupancy of grassland butterflies throughout the Northern Great Plains to assist future research. We used line-transect distance sampling (LT) and visual encounter surveys (VES), methods that account for imperfect detection, three times in June and July to find densities for common species and occupancy for rarer species at 20 sites. Additionally, we collected plant community and structure data, flowering forb density, and weather conditions to better predict detection rates. After one season, we detected 20 species of butterflies. We observed common species like cabbage whites and clouded sulphurs throughout the season, while we only detected skippers (Hesperiidae) early in the season and greater fritillaries (Heliconiinae) later in the season. We doubled the number of detections and observed twice as many species with the VES compared to the LT. Overall, we did not detect any different grassland-dependent species in one search method compared to the other. We will present detection rates and density for some common species and occupancy for some rare species. As conservation efforts increase, more background knowledge can aid and improve research objectives and design, leading to a greater understanding of grassland butterfly ecology and management strategies in the Northern Great Plains.