The population of Bays City, Ohio is 39328 people. There are 36,093 housing units in the city, of which 18,659 are owner-occupied. The remaining 17.434 are occupied by renters. The median age of the population is 33 years. The male population outnumbers the female population 94.6 to one.
A majority of Bays City's residents are white. About 65% of households were white and there were 24,018 families. The average family size was 3.43. In the census of 2000, 29.8% of households had a person under the age of 18. One in three households was headed by a woman, and a family of four represented the largest percentage of households.