Population in Castle Rock, CO

Population in Castle Rock, CO was 83,815 in 2025, according to the U.S. Census Bureau. That is up 1% from 2024. That is the 14th highest of 54 cities in 2025.

2025, persons83,815
Change on 2024+1%
Series high83,8152025
Series low73,8882020

Population in Castle Rock, CO, 2020 to 2025

72K74K76K78K80K82K84K2020202120222023202420252020: 73,888 persons2021: 76,659 persons2022: 80,164 persons2023: 81,523 persons2024: 83,004 persons2025: 83,815 persons
persons. Source: U.S. Census Bureau, Annual estimates of the resident population for incorporated places, 1 July (Population Estimates Program, subcounty totals). Retrieved 2026-10-12, published 2026-05-14.
All 6 values
Periodpersons
202583,815
202483,004
202381,523
202280,164
202176,659
202073,888

Compared with Colorado and United States

Place2025
Castle Rock, CO83,815
Colorado6,012,561
United States341,784,857

Rankings

Definition

Resident population. Spain and the EU: 1 January, with Spanish figures from the official municipal register (Padrón). Norway: Statistics Norway, 1 January. United States: Census Bureau population estimates for 1 July. United Kingdom regions and local authorities: Office for National Statistics estimates for 30 June. Other countries and the World: World Bank mid-year estimates, which count all residents regardless of legal status or citizenship.

The World Bank series exists for every country, so use it (through compare) to rank countries on one basis.

How to cite

U.S. Census Bureau. Annual estimates of the resident population for incorporated places, 1 July (Population Estimates Program, subcounty totals). https://www2.census.gov/programs-surveys/popest/datasets/2020-2025/. Retrieved 2026-10-12.

Use this data in your AI agent

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What is the latest population in Castle Rock, CO? Cite the source.
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Questions

What is the population in Castle Rock, CO?

Population in Castle Rock, CO was 83,815 in 2025, according to the U.S. Census Bureau. That is up 1% from 2024. That is the 14th highest of 54 cities in 2025.

Where does this figure come from?

U.S. Census Bureau. Annual estimates of the resident population for incorporated places, 1 July (Population Estimates Program, subcounty totals). Retrieved by Invokely on 2026-10-12.

What was the highest population in Castle Rock, CO?

83,815 in 2025, the highest value since 2020 in this series.

Population elsewhere in Colorado

All statistics for Castle Rock, CO