South Salt Lake, UT has a population of 24,575 and is the 1,770th largest city in the United States. The population density is 3,540 per sq mi which is 10424% higher than the Utah average and 3808% higher than the national average. The median age in South Salt Lake is 30 which is approximately 2% lower than the Utah average of 30. In South Salt Lake, 44% of the population over 15 years of age are married, 64% speak English and 17% speak Spanish. 47% of South Salt Lake residents were born in Utah, 25% were born out of state, 1% were born outside of the United States and 26% were foreign born.