Lamar
- County:
- Johnson County
- County Seat:
- No
- Area (mi²):
- 4.616
- State:
- Arkansas
Lamar is a city located in Johnson County, Arkansas. Lamar has a 2026 population of 1,769. Lamar is currently growing at a rate of 0.45% annually and its population has increased by 2.97% since the most recent census, which recorded a population of 1,718 in 2020.