The composition and physicochemical properties of oat flour with respect to β-glucan content and its solubility and viscosity were investigated. Eight oat cultivars grown in 20 prairie locations for three consecutive years were examined in this study to establish how cultivar, growing location, and their interaction influence the abovementioned attributes. It was found that the β-glucan content was primarily influenced by oat cultivar, while growing location and the interaction between cultivar and location had minimal effect. Among the eight cultivars, HiFi had the highest β-glucan content (5.82% w/w), while Derby had the lowest (4.37% w/w). Growing location, oat cultivar, and their interaction had a significant effect on β-glucan solubility and viscosity. The β-glucan solubility differed among oat cultivars, where 28.44-34.28% of the β-glucan present in the oat flour could be solubilized at 37°C. Viscosity was evaluated by consecutive fixed speed tests at shear rates of 1.29-129 s^-1. Results showed that shear rate, growing location, and cultivar affected viscosity. The flow behavior index (n) for all β-glucan dispersions indicated shear-thinning behavior. HiFi had the highest β-glucan solubility and viscosity among all the cultivars analyzed. The findings provide insight into raw material selection and variations in raw material characteristics when targeting specific oat product applications.