San Juan County is a county in New Mexico, United States, occupying the state’s northwestern corner and including New Mexico’s share of the Four Corners. It had a population of 121,661 at the 2020 census and covers 5,538 square miles (14,343 km2), centred near 36°31′N 108°19′W.
Aztec is the county seat, and its postal code is 87410. The county contains three cities, one town and dozens of unincorporated communities, most of them Navajo Nation chapters — the Navajo Nation covers roughly 60 percent of San Juan County’s land. San Juan County observes Mountain Time and carries FIPS code 35045.
Towns & Villages in San Juan County
San Juan County has three incorporated cities (Aztec, Bloomfield, Farmington), one incorporated town (Kirtland) and a wide scatter of census-designated places and unincorporated communities, many of them Navajo Nation chapters along the San Juan and La Plata river valleys. The table below carries every settlement verified against the current place list; a handful of entries from the old page — Alcatraz, Crystal and North Light Plant — are dropped as unverifiable or belonging to a different county or state (see notes).
| Place | Type | Pop. | ZIP |
|---|---|---|---|
| Farmington | City | 46,624 | 87401 |
| Aztec | City · seat | 6,378 | 87410 |
| Bloomfield | City | 7,724 | 87413 |
| Kirtland | Town | — | 87417 |
| Shiprock | CDP | — | 87420 |
| Waterflow | CDP | — | 87421 |
| Flora Vista | CDP | — | 87415 |
| Navajo Dam | CDP | — | 87419 |
| Nageezi | CDP | — | 87037 |
| Newcomb | CDP | — | 87455 |
| Naschitti | CDP | — | — |
| Sheep Springs | CDP | — | — |
| Upper Fruitland | CDP | — | 87416 |
| Fruitland | Unincorp. | — | 87416 |
| La Plata | CDP | — | — |
| Blanco | CDP | — | — |
| Turley | CDP | — | — |
| Sanostee | CDP | — | — |
| Crouch Mesa | CDP | — | — |
| Cedar Hill | Unincorp. | — | — |
| Angostura | Unincorp. | — | — |
| Archuleta | Unincorp. | — | — |
| Beclabito | Unincorp. | — | — |
| Center Point | Unincorp. | — | — |
| Cottonwood | Unincorp. | — | — |
| Cudei | Unincorp. | — | — |
| Fivemile Crossing | Unincorp. | — | — |
| Huerfano | Unincorp. | — | — |
| Inca | Unincorp. | — | — |
| Kimbeto | Unincorp. | — | — |
| La Boca | Unincorp. | — | — |
| Lake Valley | Unincorp. | — | — |
| Little Water | Unincorp. | — | — |
| Middle Mesa | Unincorp. | — | — |
| Napi Headquarters | Unincorp. | — | — |
| Nenahnezad | Unincorp. | — | — |
| Ojo Amarillo | Unincorp. | — | — |
| Rattlesnake | Unincorp. | — | — |
| Riverside | Unincorp. | — | — |
| South River | Unincorp. | — | — |
| Spencerville | Unincorp. | — | — |
| Toadlena | Unincorp. | — | — |
| Tocito | Unincorp. | — | — |
| Totah Vista | Unincorp. | — | — |
| Tsaya | Unincorp. | — | — |
| Two Grey Hills | Unincorp. | — | — |
| West Hammond | Unincorp. | — | — |
| White Rock | Unincorp. | — | — |
Fruitland and Upper Fruitland are two adjoining places sharing the same 87416 ZIP; treat them as distinct communities on the ground but one postal area. White Rock in San Juan County is a small local place name unrelated to the better-known White Rock CDP in Los Alamos County.
ZIP Codes
- 87410 — Aztec (also serves nearby rural addresses)
- 87401 — Farmington (the city’s main ZIP)
- 87413 — Bloomfield
- 87417 — Kirtland
- 87420 — Shiprock
- 87421 — Waterflow
- 87415 — Flora Vista
- 87419 — Navajo Dam
- 87416 — Fruitland (also serves Upper Fruitland)
- 87455 — Newcomb
- 87037 — Nageezi
Smaller unincorporated communities such as Blanco, Cedar Hill, Sanostee and Turley are generally served by the ZIP code of the nearest listed post office town rather than a code of their own.
Geography
San Juan County lies in New Mexico’s northwest corner, where the San Juan and Animas rivers meet near Farmington and the La Plata River enters from Colorado. The county holds New Mexico’s only piece of the Four Corners, the single point in the United States where four states meet. Terrain ranges from the irrigated river bottoms around Farmington and Aztec to the high desert mesas of the San Juan Basin and the Chuska Mountains along the Arizona line; Shiprock Pinnacle, a volcanic plug sacred to the Navajo, rises from the plain near the town of the same name. Indian reservation land, almost all Navajo Nation, covers about 63 percent of the county.
San Juan County borders Rio Arriba County to the east, Sandoval County to the southeast, McKinley County to the south, Apache County, Arizona, to the west, San Juan County, Utah, to the northwest, and Montezuma, La Plata and Archuleta counties, Colorado, to the north and northeast.
Demographics
San Juan County had 121,661 residents at the 2020 census, the fifth-highest county total in New Mexico. Farmington, with 46,624 people, is by far the largest community; Bloomfield, at 7,724, is the second largest. Median household income in the county runs below the New Mexico median of $62,268, reflecting the mix of oil-field wages and lower-income reservation communities. Population density works out to roughly 22 people per square mile of land, concentrated heavily in the Farmington-Aztec-Bloomfield corridor along US-64 and US-550.
Economy & Local Life
San Juan County sits atop the San Juan Basin, one of the country’s major natural-gas and coalbed-methane fields, and oil and gas extraction remains a leading employer alongside pipeline and services work. Coal-fired power once anchored the county’s economy at the Four Corners Power Plant and the San Juan Generating Station near Waterflow; the Generating Station ceased coal operations in 2022 as utilities shift to other sources. San Juan Regional Medical Center and San Juan College, both in Farmington, are among the county’s largest non-energy employers, and the Navajo Nation government and its enterprises are major employers on the western side of the county. Farmington functions as the retail, medical and cultural hub for the wider Four Corners region.
History
San Juan County was organized in 1887, taking its name from the San Juan River, which Spanish explorers named for Saint John. The area sits within the greater Chaco region: Chaco Culture National Historical Park, a UNESCO World Heritage Site preserving major ancestral Puebloan great houses, is reached from the county through Nageezi. Farmington and the surrounding valley grew slowly as an agricultural settlement through the early 1900s before an oil and natural-gas boom, beginning in the 1950s, transformed the county into an energy-producing region. Much of the county’s land remains part of the Navajo Nation’s checkerboard reservation, and land and water-rights questions tied to that status continue to shape local politics.
Getting There
US-64 crosses the county east-west through Farmington and Shiprock, US-550 runs southeast from Bloomfield toward Albuquerque, and US-491 runs south from Shiprock toward Gallup.
- Durango, Colorado — about 45 miles north
- Gallup — about 90 miles south
- Albuquerque — about 180 miles southeast
- Cortez, Colorado — about 50 miles northwest
Four Corners Regional Airport (FMN) in Farmington offers commercial flights to Denver.
Frequently Asked Questions
Where is San Juan County, New Mexico?
It sits in the state’s northwestern corner, holding New Mexico’s share of the Four Corners, where New Mexico, Colorado, Utah and Arizona meet.
What is the population of San Juan County?
121,661 people at the 2020 census, the fifth-highest county total in New Mexico.
How big is San Juan County?
5,538 square miles (14,343 km2), of which 5,513 square miles are land and 25 square miles are water.
What is the county seat of San Juan County?
Aztec is the county seat; Farmington, just south of Aztec, is the county’s largest city.
How many towns and cities are in San Juan County?
Three cities — Aztec, Bloomfield and Farmington — plus the town of Kirtland and dozens of unincorporated communities and Navajo Nation chapters.
What ZIP codes are in San Juan County?
Main ZIP codes include 87410 (Aztec), 87401 (Farmington), 87413 (Bloomfield), 87417 (Kirtland), 87420 (Shiprock) and 87421 (Waterflow), among others.
Is Chaco Culture National Historical Park in San Juan County?
Yes — the park is reached through the county, via the community of Nageezi off US-550.
More counties in this state: Towns and villages in New Mexico.