California Population By County 2025. California’s population declined by 37,200 between july 1, 2022 and july 1, 2023, to total 39.11 million, according to official. For the most recent data available, please refer to the vintage 2023 data.

Riverside county, california ‘s estimated 2025 population is 2,510,643 with a growth rate of 0.73% in the past year according to the most recent united states census data. This report provides population estimates for january 1, 2021 through january 1, 2023 and provisional population estimates for january 1, 2025, for the state, counties, and cities.