2 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Rexburg | 1 | 40,927 | 39,764 | 0.57% | 4,047 | 10 | City |
| Sugar City | 2 | 2,560 | 1,733 | 6.89% | 1,290 | 2 | City |
Rexburg is the largest city in Madison County, with a population of 40,927.
Sugar City is the smallest city in Madison County, with a population of 2,560.
There are 2 cities in Madison County, Idaho.