Williston, FL has a population of 2,740 and is the 9,268th largest city in the United States. The population density is 407 per sq mi which is 39% higher than the Florida average and 349% higher than the national average. The median age in Williston is 33 which is approximately 22% lower than the Florida average of 42. In Williston, 47% of the population over 15 years of age are married, 92% speak English and 7% speak Spanish. 69% of Williston residents were born in Florida, 24% were born out of state, 2% were born outside of the United States and 4% were foreign born.