Waialua, HI has a population of 3,769 and is the 7,714th largest city in the United States. The population density is 1,720 per sq mi which is 1250% higher than the Hawaii average and 1799% higher than the national average. The median age in Waialua is 40 which is approximately 4% higher than the Hawaii average of 39. In Waialua, 59% of the population over 15 years of age are married, 70% speak English and 2% speak Spanish. 54% of Waialua residents were born in Hawaii, 21% were born out of state, 2% were born outside of the United States and 24% were foreign born.