Plain

County ZIP codes · Colorado · FIPS 08003

Alamosa County, CO ZIP Codes

Alamosa County, Colorado has 6 ZIP codes (Census 2020 ZCTA-county file; GeoNames postal codes, October 2026): 5 residential and 1 for PO boxes or a single organization. 3 of the residential ones lie mainly in Alamosa County and 2 mainly in a neighboring county; 4 cross the county line. Median household income ranges from $54,844 in 81101 (Alamosa) to $64,662 in 81144 (Monte Vista) (Census Bureau, ACS 2020-2024).

  • ACS2020-24
  • Census2020

Where are the ZIP codes of Alamosa County?

81101 · Alamosa: $55k81125 · Center: $56k81136 · Hooper: $47k81144 · Monte Vista: $65k81146 · Mosca: $70k811018114681144811258113681101 · Alamosa: $55k81125 · Center: $56k81136 · Hooper: $47k81144 · Monte Vista: $65k81146 · Mosca: $70k811018114681144811258113681101 · Alamosa: $55k81125 · Center: $56k81136 · Hooper: $47k81144 · Monte Vista: $65k81146 · Mosca: $70k8110181146811448112581136
The residential ZIP codes of Alamosa County (whole outlines, including the parts in neighboring counties), shaded by median household income in national fifths (ACS 2020-2024).<$54.1k$98.1k+no figure

Source: U.S. Census Bureau, 2020 ZCTA cartographic boundaries; ACS 2020-2024 5-year estimates (B19013).

How different are its ZIP codes?

They carry 5 postal town names: Alamosa, Monte Vista, Center, Mosca, Hooper.

Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B19013).

All 5 residential ZIP codes in Alamosa County

3 ZIP codes lie mainly in Alamosa County; 2 more reach into it from a neighboring county and follow the first table.

Residential ZIP codes mainly in Alamosa County, largest first; "In this county" is the share of the ZIP's land in the county
In this county
81101 Alamosa 15,550 42 $55k $240k 94%
81146 Mosca 637 2 $70k $232k 100%
81136 Hooper 305 4 $47k $193k 80%

Partly in Alamosa County

Residential ZIP codes mainly in another county that reach at least 1% into Alamosa County, by their share here
In this county
81144 Monte Vista 6,543 23 $65k $234k 8%
81125 Center 3,362 13 $56k $149k 2%

Download the 6 ZIP codes as CSV

Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates; county shares by land area (Census 2020 ZCTA-county relationship file).

Which ZIP codes cross the county line?

4 ZIP codes of Alamosa County extend into another county. A ZIP code follows mail routes, not county borders.

Share of each ZIP code's land in Alamosa County and in the neighboring counties
ZIPIn AlamosaElsewhere
8110194%Conejos County6%
811448%Rio Grande County92%
811252%Saguache County82%; Rio Grande County17%
8113680%Saguache County20%

Source: U.S. Census Bureau, 2020 ZCTA-county relationship file (shares of land area).

PO Box and single-organization ZIP codes

ZIP codes in Alamosa County without a residential area (GeoNames postal codes)
ZIPPostal name
81102Alamosa

Source: GeoNames postal codes (CC BY 4.0).

Which first three digits do Alamosa County's ZIP codes use?

The first three digits of a ZIP code name the sectional center, the mail processing plant that sorts it. Every ZIP code of Alamosa County starts with 811.

Three-digit prefixes of Alamosa County's ZIP codes, the sectional center for each (USPS labeling list L005, effective October 1, 2026) and how many of the prefix's codes are Alamosa County's
PrefixSectional centerHereAll codes
811Colorado Springs, CO (SCF 808)632

Source: U.S. Postal Service, labeling list L005 (3-digit ZIP Code prefix groups, SCF sortation), effective October 1, 2026.