Trenton
- County:
- Grundy County
- County Seat:
- Yes
- Area (mi²):
- 6.447
- State:
- Missouri
Trenton is a city located in Grundy County, Missouri. Trenton has a 2026 population of 5,588. It is also the county seat of Grundy County. Trenton is currently declining at a rate of -0.46% annually but its population has increased by 0.11% since the most recent census, which recorded a population of 5,582 in 2020.