More awareness from consumers on the health benefits of oat (Avena sativa L.) in the last few decades has increased the demand for oat. However, in the United States, oat production has continued to decline. Most of the oats used in U.S. food products are imported from Canada. Although oats are known to fit well in corn (Zea mays L.)–soybean [Glycine max (L.) Merr] rotations, difficulties in marketing the grain and relatively low prices in comparison to corn and soybeans have limited the number of acres planted to oats. High‐yielding oat cultivars adapted to the Northern Great Plains with high test weight and good milling characteristics are needed. ‘Rushmore’ (Reg. no. CV‐388, PI 698122) is a spring oat cultivar released by the South Dakota Agricultural Experiment Station in 2019. Rushmore was derived from the three‐way cross SD080015//SD070110/SD060130 and developed using a modified bulk and single‐seed descent method. Prior to release, Rushmore was tested in the uniform early oat performance nursery in 2016 and 2017 and in the South Dakota Crop Performance Testing oat variety trial since 2017. Rushmore was evaluated as experimental line SD140515 and evaluated for grain yield, test weight, disease resistance, lodging resistance, grain shape, milling characteristics, and grain composition. Rushmore was released to oat producers due to its combination of high grain yield, excellent test weight, lodging and disease resistance, and good milling characteristics. The excellent test weight potential of Rushmore is expected to help producers in marketing their grain to the feed and food industries.