St. Louis city area

Population and density of St. Louis city

The Census Bureau estimates that 278,144 people lived in St. Louis city on July 1, 2025. That ranks #266 of 3,222 county equivalents nationally and #5 of 115 in Missouri. Since the April 1, 2020 estimates base of 301,349, the population has declined by 23,205 (−7.7%), compared with +1.9% for Missouri as a whole.

With 61.7 square miles of land, that is 4,507 people per square mile (1,740 per km²), placing St. Louis city #22 nationally for density and #1 in Missouri. The median county equivalent has 47 people per square mile; the Missouri median is 31. Put another way, there are about 0.142 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 St. Louis city

Every resident of St. Louis city lives within St. Louis city. The city and the county equivalent cover the same territory, 61.7 square miles of land in the 2026 place Gazetteer, so there are no separate towns or unincorporated areas to list.

Metropolitan area

St. Louis city is a central county of the St. Louis, MO-IL Metropolitan Statistical Area. Its 15 county equivalents have 2,814,421 residents on 7,863.5 square miles of land; St. Louis city accounts for 0.8% of the land and 9.9% of the residents. By combined land it ranks #19 of 393 metropolitan areas, and #23 by population. It belongs to the St. Louis-St. Charles-Farmington, MO-IL Combined Statistical Area.

ZIP codes

30 ZIP Code Tabulation Areas have land in St. Louis city; 19 of them have most of their land inside the county, and the others mainly cover neighboring areas.

631016310263103631046310563106631076310863109631106311163112631136311563116631176311863119631206312363125631306313363136631376313863139631436314763155

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 St. Louis city

St. Louis city shares a land border with 3 county equivalents, including 2 in Illinois. Each of them has more land than St. Louis city. The largest neighbor is Madison County (715.5 mi²) and the smallest is St. Louis County (508.5 mi²). Together with its neighbors, St. Louis city forms a block of 1,943.5 mi² of land, of which it holds 3.2%.

How big is St. Louis city compared with U.S. states?

St. Louis city has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 17 times as much. Missouri’s county land could hold about 1,114 areas the size of St. Louis city.

Another way to picture it: the same land area would fill a square about 7.86 miles (12.6 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 St. Louis city?

St. Louis city has more land than 111 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 St. Louis city at #3,137 nationally by total area, 26 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 6.7%, compared with a national county-equivalent median of 1.2% — 5.6 percentage points higher. 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 St. Louis city 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.