Solubilities of sodium chlorate were measured in chloric acid solutions ranging in concentration from 5 to 22 mass % HClO3 at temperatures of 25, 35, 45, 55, and 65 degrees C. Densities of saturated solutions were determined by weighing measured volumes of the solutions. Densities of chloric acid solutions and unsaturated chloric acid + sodium chlorate solutions were determined at 25 degrees C over a range of solution concentrations using a digital density meter. The solubility data and previously reported data from Literature sources were correlated with chloric acid concentration and temperature by multilinear regression. All of the data could be represented graphically by a single line by plotting the ratio of sodium chlorate solubility in chloric acid solution to sodium chlorate solubility in water versus mass percent chloric acid. The specific volume of chloric acid at 25 degrees C is linear with respect to chloric acid concentration. A parameter determined from the slope of this linear plot and the density of crystalline sodium chlorate were used to correlate densities of chloric acid solutions containing sodium chlorate.