Population Demographics
As of 2025 the population of Columbia County is 65,377. The population is expected to grow to 65,401 by 2030 - a growth rate of 0.01%.
The median age of Columbia County residents is 42.
The diversity index of Columbia County is 23.9, meaning that there is a 24% chance that any two people selected out of 100 residents will be of different race or ethnicity from one another.