Every ZIP code in the United States, with weather, radar, trivia and the numbers behind it. Five digits since 1963!

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Union County, NM ZIP codes

There are 7 ZIP codes in Union County, NM, in 7 towns, from 88410 to 88436. The largest are 88415 (Clayton), 88418 (Des Moines) and 88410 (Amistad).

The county seat is Clayton.

ZIP codes
7
Towns
7
County seat
Clayton
County FIPS
35059
Population
4,013
Median household income
$46,694
Land area
3,825 sq mi

Union County ZIP codes by town

Clayton (county seat)
88415

Each ZIP code is listed under the county most of its land lies in and the town the Postal Service names it for; a ZIP code's own page shows exactly how it is split.

Map of Union County ZIP codes

88410884158841888419884228842488436

The ZIP codes of Union County, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.

Union County in numbers

About 4,013 people live in Union County, in 1,438 households, the 30th most populous of New Mexico's 33 counties. The median household income is $46,694 a year, 27% below the New Mexico median of $64,059 (US: $80,734). The median owner-occupied home is valued at $122,700 (51% below the New Mexico median), and median gross rent is $683 a month. The median age is 42.6; 18.4% of adults 25 and over hold a bachelor's degree or higher (31.0% across New Mexico); the average commute takes 17 minutes.

Population4,013Union4,013
Households1,438Union1,438
Median age42.6Union42.6New Mexico39.4US 38.9
Median household income$46,694Union$46,694New Mexico$64,059US $80,734
Median home value$122,700Union$122,700New Mexico$248,100US $332,700
Median gross rent$683Union$683New Mexico$1,067US $1,413
Bachelor's degree or higher18.4%Union18.4%New Mexico31.0%US 35.7%
Mean commute16.7 minUnion16.7 minNew Mexico23.5 minUS 26.4 min
Population density1 / sq miUnion1 / sq mi

U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates. Survey estimates carry margins of error, wider for small places. Sources and methods.

Largest towns in Union County

Largest towns in Union County
TownZIP codesPopulation
Clayton 1 2,753
Des Moines 1 174
Gladstone 1 117
Grenville 1 56
Amistad 1 45
Sedan 1 25
Folsom 1 11

Population of the census place of that name where there is one, otherwise of the ZIP codes the Postal Service addresses by it. A town's ZIP codes can reach past the county line.

Neighbouring counties

Counties that share a ZIP code with Union County.

Not sure you are in Union County? What county am I in? answers from your location, near a county line included.

Every ZIP code in Union County, with figures

ZIP codes in Union County
ZIP City Type Population Median income Median home
88410 Amistad , NM Standard 45 $36,042 —
88415 Clayton , NM Standard 3,178 $44,952 $120,800
88418 Des Moines , NM Standard 536 $77,813 $165,400
88419 Folsom , NM Standard 61 $96,250 $252,100
88422 Gladstone , NM Standard 117 $61,346 $116,300
88424 Grenville , NM Standard 89 — —
88436 Sedan , NM Standard 25 — —

Cite this page

zipcodes.pro. “Union County ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/nm/county/union

Underlying data is public domain or openly licensed — sources, vintages and licences.