| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Neosho | 1 | 14,346 | 12,726 | 1.9% | 921 | 16 | City |
| Seneca | 2 | 2,363 | 2,252 | 0.85% | 923 | 3 | City |
| Granby | 3 | 2,125 | 2,050 | 0.57% | 480 | 4 | City |
| Diamond | 4 | 920 | 834 | 1.55% | 1,232 | 1 | Town |
| Fairview | 5 | 434 | 419 | 0.46% | 919 | 0 | Town |
| Saginaw | 6 | 339 | 300 | 1.8% | 411 | 1 | Village |
| Newtonia | 7 | 216 | 208 | 0.47% | 663 | 0 | Town |
| Stella | 8 | 171 | 165 | 0.59% | 1,049 | 0 | Town |
| Stark City | 9 | 131 | 127 | 0% | 402 | 0 | Town |
| Ritchey | 10 | 72 | 70 | 0% | 1,469 | 0 | Town |
Neosho is the largest city in Newton County, with a population of 14,346.
Ritchey is the smallest city in Newton County, with a population of 72.
There are 10 cities in Newton County, Missouri.