McArthur, CA has a population of 481 and is the 19,767th largest city in the United States. The population density is 480 per sq mi which is 107% higher than the California average and 430% higher than the national average. The median age in McArthur is 46 which is approximately 28% higher than the California average of 36. In McArthur, 74% of the population over 15 years of age are married, 88% speak English and 12% speak Spanish. 68% of McArthur residents were born in California, 22% were born out of state, 0% were born outside of the United States and 10% were foreign born.