In 2022, the population of Hartly was 76, a 4.11% increase year-by-year from 2021. Previously, in 2021, Hartly's population was 73, an increase of 1.39% compared to a population of 72 in 2020.
The median age in Hartly, DE is 43.2, as per 2021 ACS 5-Year Estimates. Of the total population, 2.45% were under the age of 15, 39.88% aged 15 to 29, 54.60% aged 30 to 64, 3.07% aged 65 to 84, and 0.00% were 85 years of age and older.