By Zach Wennstedt, founder of Eye To Ad Media · September 29, 2026
Castle Rock, Colorado had an estimated 83,815 residents in July 2025, up 14.6% from the 2020 Census count of 73,158 and up from 48,231 in 2010, according to the U.S. Census Bureau. The town has 28,219 households, averaging 2.78 people each, and a median household income of $145,197, compared with $95,470 statewide.
Numbers do not sell anything by themselves. But they tell you who you are selling to, and these ones say a lot.
A town that keeps growing
The Census counted 48,231 people in Castle Rock in 2010 and 73,158 in 2020. By July 2025 the estimate was 83,815. That is a lot of new neighbors who have not picked their dentist, plumber, gym or favorite restaurant yet, and new residents search for almost everything.
Households, not just people
For most local businesses, the buying unit is the household. Castle Rock has 28,219 of them, with 2.78 people per household on average, above the Colorado figure of 2.42. Bigger households mean more of the services families buy: kids' activities, home services, healthcare, food.
A high-income market
Median household income in Castle Rock is $145,197, compared with $95,470 for Colorado and $80,734 for the U.S. High-income buyers tend to research carefully and pay for quality, which rewards businesses with detailed pages, real reviews and clear pricing ranges.
What it means for your marketing
- New residents search first. Being in the Map Pack is worth more here than in a stable town.
- Careful buyers read. Thin pages and stock photos lose to specific, honest content.
- Competition follows growth. More businesses are moving in to serve these households, so local SEO gets harder every year you wait.
Put your own numbers against these with the free Castle Rock market size calculator.