Grand Bay, AL has a population of 3,841 and is the 7,626th largest city in the United States. The population density is 443 per sq mi which is 381% higher than the Alabama average and 389% higher than the national average. The median age in Grand Bay is 40 which is approximately 3% higher than the Alabama average of 39. In Grand Bay, 61% of the population over 15 years of age are married, 100% speak English and 0% speak Spanish. 57% of Grand Bay residents were born in Alabama, 42% were born out of state, 0% were born outside of the United States and 1% were foreign born.