CENSUS DATA REVEALS JOHNSTON’S POPULATION GREW BY 39 PERCENT
The official 2020 census data reveals the population for the City of Johnston is now 24,064. This is a 39.3 percent increase from the 2010 data, which was 17,278. Johnston is now the fifth fastest-growing city in Polk County.
Below is a table on the population by city in Polk County.
| City | 2020 | 2010 | Percent Change |
| Bondurant | 7,365 | 3,860 | 90.8% |
| Grimes | 15,392 | 8,246 | 86.7% |
| Polk City | 5,543 | 3,418 | 62.2% |
| Ankeny | 67,887 | 45,582 | 48.9% |
| Johnston | 24,064 | 17,278 | 39.3% |
| Altoona | 19,565 | 14,541 | 34.6% |
| Elkhart | 882 | 683 | 29.1% |
| West Des Moines | 68,723 | 56,609 | 21.4% |
| Clive | 18,601 | 15,447 | 20.4% |
| Pleasant Hill | 10,147 | 8,875 | 15.5% |
| Urbandale | 45,580 | 39,463 | 15.5% |
| Mitchellville | 2,485 | 2,254 | 10.2% |
| Windsor Heights | 5,252 | 4,860 | 8.1% |
| Des Moines | 214,133 | 203,433 | 5.3% |
More information about the census data is available by visiting the Iowa State University Extension.