County data kits / Finding 001
California | July 2023 to July 2024
Santa Clara added the most residents. Placer grew fastest.
Across California’s 58 counties, Santa Clara added an estimated 29,188 residents from July 2023 to July 2024. Placer added 9,223, a 2.17% increase from its smaller starting population.
The 825 | Published November 1, 2026 | Census Vintage 2024
This finding uses the 2024 release so its figures can be reproduced from the linked kits. The Census Bureau has since published county estimates through July 2025.
Two ways to read the same year
For a planner asking how many additional people a county serves, count residents. For a planner asking how quickly the population changed relative to its size, divide by the starting population. Yuba illustrates the difference: 1,774 additional residents put it second statewide by percentage growth.
| County | July 2023 estimate | Residents added | Growth |
|---|---|---|---|
| Santa Clara County | 1,897,137 | +29,188 | 1.54% |
| Riverside County | 2,503,549 | +26,384 | 1.05% |
| Los Angeles County | 9,731,837 | +25,342 | 0.26% |
| Sacramento County | 1,594,506 | +16,725 | 1.05% |
| Orange County | 3,154,563 | +15,872 | 0.50% |
| County | July 2023 estimate | Residents added | Growth |
|---|---|---|---|
| Placer County | 424,599 | +9,223 | 2.17% |
| Yuba County | 85,695 | +1,774 | 2.07% |
| Del Norte County | 26,571 | +438 | 1.65% |
| Santa Clara County | 1,897,137 | +29,188 | 1.54% |
| San Joaquin County | 805,909 | +10,199 | 1.27% |
Sources and calculation
Source: U.S. Census Bureau, county population estimates, Vintage 2024. Filter the original county estimates CSV to California (STATE 06) and counties (SUMLEV 050). Subtract POPESTIMATE2023 from POPESTIMATE2024. Divide that difference by POPESTIMATE2023 and multiply by 100 for percentage growth. Rank all 58 counties before rounding. These estimates describe total population change. They cannot by themselves explain migration or changes in service demand.
Suggested citation: The 825, “Santa Clara added the most residents. Placer grew fastest.” Finding 001, November 1, 2026. Calculations from U.S. Census Bureau Vintage 2024 estimates.
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Request a correction at jovan@the825.co. Include Finding 001 and the county or figure in question.
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