Chlosyne acastus, the sagebrush checkerspot, is a butterfly of the family Nymphalidae that is found in North America. They range from western United States east to Nebraska and north to southern Alberta.
The adult may be often confused with the northern checkerspot (C. palla) and Hoffmann's checkerspot (C. hoffmanni). The adult's wingspan is .
There is one flight that occurs between May and early September in Canada. The caterpillar of this species feeds on rabbit-brush (Chrysothamnus viscidiflorus) and desert-aster (Machaeranthera species).