San Miguel County area

Population and density of San Miguel County

The Census Bureau estimates that 26,260 people lived in San Miguel County on July 1, 2025. That ranks #1,615 of 3,222 county equivalents nationally and #17 of 33 in New Mexico. Since the April 1, 2020 estimates base of 27,205, the population has declined by 945 (−3.5%), compared with +0.4% for New Mexico as a whole.

With 4,721.5 square miles of land, that is 5.6 people per square mile (2.1 per km²), placing San Miguel County #2,822 nationally for density and #20 in New Mexico. The median county equivalent has 47 people per square mile; the New Mexico median is 6.9. Put another way, there are about 115 acres of land per resident.

U.S. Census Bureau, Vintage 2025 population estimates. Estimates are revised each year and are not decennial census counts. Density divides the whole population by the whole county’s land area, so it describes an average, not how settlement is distributed within the county. Population sources and methods.

Cities and towns in San Miguel County

3 incorporated places lie at least partly in San Miguel County. Together they are home to 13,949 people (53.1%); the other 12,311 (46.9%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Las Vegas city, with 12,574 residents in the county.

Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each place inside San Miguel County. Land: 2026 Census Gazetteer, for the whole place even where it extends into other counties. How communities are listed.

Metropolitan area

San Miguel County is a central county of the Las Vegas, NM Micropolitan Statistical Area. Its 2 county equivalents have 30,311 residents on 6,647.8 square miles of land; San Miguel County accounts for 71% of the land and 86.6% of the residents. By combined land it ranks #12 of 542 micropolitan areas, and #435 by population. It belongs to the Albuquerque-Santa Fe-Los Alamos, NM Combined Statistical Area.

ZIP codes

23 ZIP Code Tabulation Areas have land in San Miguel County; 17 of them have most of their land inside the county, and the others mainly cover neighboring areas.

8705687535875388755287560875628756587569875738758387701877118773187742877458774688321884018841688421884268843188439

ZIP Code Tabulation Areas are the Census Bureau’s approximations of USPS ZIP Code service areas, from the 2020 Census relationship files. Lighter codes have less than half of their land in this county. Post-office-box and single-address ZIP Codes have no tabulation area.

Counties bordering San Miguel County

San Miguel County shares a land border with 6 county equivalents. It has more land than every one of them. The largest neighbor is Torrance County (3,345.2 mi²) and the smallest is Santa Fe County (1,910.4 mi²). Together with its neighbors, San Miguel County forms a block of 19,932.6 mi² of land, of which it holds 23.7%.

How big is San Miguel County compared with U.S. states?

San Miguel County has more land than 2 of the 50 states. It is about 2.4 times the land area of Delaware (1,948.6 mi²), while Connecticut, the next larger state, has 1 times as much land (4,842.5 mi²). New Mexico’s county land could hold about 26 areas the size of San Miguel County.

Another way to picture it: the same land area would fill a square about 68.7 miles (110.6 km) on each side. Real county shapes are rarely square, so this is a scale reference rather than a width or driving distance.

State figures are the sums of each state’s county-equivalent land measurements in the same Census release, so states and counties are compared on the same basis. Published state totals can differ slightly because of rounding. Compare all states · Counties bigger than entire states.

What stands out about San Miguel County?

San Miguel County has more land than 3,130 of the other 3,221 county equivalents in the dataset.

A median is the middle county-equivalent measurement, not the average of the largest and smallest. All three bars use the same linear scale. Very small areas may appear as a thin sliver; the labels retain their values.

Does including water change its rank?

Using land plus water places San Miguel County at #100 nationally by total area, 8 places farther from the top than its land rank. Other county equivalents gain more area when their water measurements are included.

Its water share is 0.4%, compared with a national county-equivalent median of 1.2% — 0.8 percentage points lower. This describes the statistical geography’s land/water mix, not flood exposure or developable land.

Closest positions in the national land ranking

These entries sit immediately beside San Miguel County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Calculated from the same Census release as the area table. Total-area order uses original ALAND + AWATER; water shares and chart labels use published square miles. Calculation details.