Sidney, NE has a population of 6,875 and is the 5,243rd largest city in the United States. The population density is 919 per sq mi which is 3732% higher than the Nebraska average and 914% higher than the national average. The median age in Sidney is 40 which is approximately 11% higher than the Nebraska average of 36. In Sidney, 62% of the population over 15 years of age are married, 94% speak English and 4% speak Spanish. 61% of Sidney residents were born in Nebraska, 36% were born out of state, 0% were born outside of the United States and 2% were foreign born.