ZIP Codes of Douglas County, CO

Population & People
Population & People
Total Population
373,996
Household Income
Household Income
Median Income
$149,273
Housing
Housing
Total Housing Units
141,796
Business & Economy
Business & Economy
Total Businesses
10,192
Employment
Employment
Employment Rate
68.92%
Education
Education
Bachelor's Degree+
61.92%
Source: U.S. Census ACS 2024 5-Year Estimates · rolled up across the 15 ZIPs in this county.
Data Last Updated: June 1, 2026
ZIP Codes:15 ZIP Codes (13 Standard, 2 PO Box, 0 Unique) [See All]
Area Codes:303 / 720 / 983
Timezone:Mountain (GMT -07:00)
Local Time:11:52:50 PM
Population:373,996 [See All]
FIPS:08035
CBSA:Denver-Aurora-Centennial, CO
Land Area:895 sq mi
Water Area:4 sq mi
Coordinates:39.4379, -104.9033
Quick Link:
https://www.zip-codes.com/county/co-douglas.asp
Need Douglas data in your app? Look up ZIP, county, and city data with a single API call.
Try Free
Among America's 25 most-educated counties
#19 nationwide — 61.9% bachelor's+.
Among America's 50 wealthiest counties
#22 nationwide, average median income $149,273.
Among Colorado's 5 fastest-growing counties
#3 statewide, up 23.9% from 2014 to 2024.
Among Colorado's 10 most populous counties
#6 of 65 counties with 373,996 residents.
Wide geographic spread
ZIPs range from 318.2 sq mi down to 4.79 — a 66× sprawl ratio.

Standout ZIPs in this County


Most Populous
Parker · 80,302 people
21.5% of county total
Highest Income
Castle Rock · $181,049 median
1.2× county average
Largest Land Area
Sedalia · 318.2 sq mi
Spans the most ground
Fastest Growth
Castle Rock · 53.4% (10-yr)
23,949 → 36,730 residents
Most Educated
Littleton · 69.8% bachelor's+
11,765 of 16,852 adults 25+

Things worth knowing about Douglas County


373,996 residents live across 15 ZIPs covering 895 sq mi, served by 8 distinct USPS-recognized cities.

Population moved from 301,956 to 373,996 from 2014 to 2024 — a +23.9% change. 13 ZIPs gained residents, 1 lost.

The county's wealthiest ZIP 80108 (Castle Rock, $181,049 median) and poorest ZIP 80124 (Lone Tree, $129,858) are 6.1 miles apart — a 1.4× income gap across local geography.

Median home values vary 1.5× across this county — from $624,200 in 80104 (Castle Rock) to $960,400 in 80116 (Franktown).

Density varies 397× across the county — from 13 people/sq mi in 80135 (Sedalia) to 5,164 in 80130 (Littleton).

Most of the decade's growth concentrated around Castle Rock — top growth ZIPs averaged +50.4% over the past ten years ( 80108 , 80109 and 80125 ).

Educational attainment ranges from 51.1% bachelor's+ in 80138 (Parker) to 69.8% in 80130 (Littleton) — the breadth of educational profiles across the area.

Within Colorado, this is the #6 most populous of 65 counties and ranks #1 for median household income with the #3 fastest decade growth .

On the national stage, Douglas County is ranks #22 for income .

Weighted by population, the typical household earns about $152,846 across the county — reflecting what a typical resident sees, not a simple ZIP average.

61.9% of adults age 25+ hold a bachelor's degree or higher (158,919 of 256,648 reporting). The most-educated ZIPs cluster around Littleton.

13 Standard delivery, 2 PO Box only, 0 single-entity Unique ZIPs serve this county.

Stories about Douglas County


Higher-education hub

9 ZIPs in this county where more than 60% of adults 25+ hold a bachelor's degree — typically college campuses, research enclaves, or tech corridors.

Littleton
69.8%
24,719 residents
Littleton
69.4%
44,882 residents
Lone Tree
66.9%
22,555 residents
Castle Rock
65.5%
36,730 residents
Littleton
64.9%
15,630 residents
Littleton
64.3%
30,223 residents
Larkspur
62.7%
5,632 residents
Franktown
60.8%
5,132 residents
Parker
60.7%
80,302 residents

Where the growth lives

Douglas County grew 23.9% over the past decade — concentrated in 5 high-growth ZIPs:

Castle Rock
+53.4%
23,949 → 36,730 residents
Castle Rock
+49.6%
18,986 → 28,400 residents
Littleton
+48.3%
10,540 → 15,630 residents
Parker
+37.9%
58,232 → 80,302 residents
Franktown
+35.1%
3,800 → 5,132 residents

All ZIP Codes in Douglas County


ZIPCityTypePopulationMedian IncomeArea (sq mi)10-yr Growth
80134ParkerStandard80,302$146,77852.137.9%
80126LittletonStandard44,882$169,88211.77.7%
80104Castle RockStandard38,479$134,33573.034.7%
80138ParkerStandard36,895$145,01360.920.2%
80108Castle RockStandard36,730$181,04941.153.4%
80129LittletonStandard30,223$141,6676.87.5%
80109Castle RockStandard28,400$155,02525.949.6%
80130LittletonStandard24,719$158,7414.8-14.1%
80124Lone TreeStandard22,555$129,85811.517.0%
80125LittletonStandard15,630$179,98345.548.3%
80118LarkspurStandard5,632$158,155152.34.7%
80116FranktownStandard5,132$146,00090.535.1%
80135SedaliaStandard4,141$136,083318.27.4%
80131LouviersPO Box276$107,2500.791.7%
80163LittletonPO Box0.0

Adjacent & Nearby Counties