Nassau Bay, TX has a population of 4,091 and is the 7,347th largest city in the United States. The population density is 3,353 per sq mi which is 3359% higher than the Texas average and 3601% higher than the national average. The median age in Nassau Bay is 42 which is approximately 24% higher than the Texas average of 34. In Nassau Bay, 46% of the population over 15 years of age are married, 81% speak English and 14% speak Spanish. 42% of Nassau Bay residents were born in Texas, 43% were born out of state, 1% were born outside of the United States and 13% were foreign born.