Guaynabo Municipio area

Population and density of Guaynabo Municipio

The Census Bureau estimates that 89,055 people lived in Guaynabo Municipio on July 1, 2025. That ranks #680 of 3,222 county equivalents nationally and #6 of 78 in Puerto Rico. Since the April 1, 2020 estimates base of 89,785, the population has declined by 730 (−0.8%), compared with −3.1% for Puerto Rico as a whole.

With 27.6 square miles of land, that is 3,232 people per square mile (1,248 per km²), placing Guaynabo Municipio #36 nationally for density and #5 in Puerto Rico. The median county equivalent has 47 people per square mile; the Puerto Rico median is 754. Put another way, there are about 0.198 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 Guaynabo Municipio

Puerto Rico has no incorporated places below the municipio: Guaynabo Municipio is itself the local government. The Census Bureau describes the settlements inside it, such as zonas urbanas and comunidades, as statistical places, and publishes no separate annual estimates for them.

Metropolitan area

Guaynabo Municipio is a central county of the San Juan-Bayamón-Caguas, PR Metropolitan Statistical Area. Its 40 county equivalents have 2,024,195 residents on 1,437.8 square miles of land; Guaynabo Municipio accounts for 1.9% of the land and 4.4% of the residents. By combined land it ranks #229 of 393 metropolitan areas, and #36 by population. It belongs to the San Juan-Bayamón, PR Combined Statistical Area.

ZIP codes

10 ZIP Code Tabulation Areas have land in Guaynabo Municipio; 6 of them have most of their land inside the county, and the others mainly cover neighboring areas.

00725009260093400959009620096500966009680096900971

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 Guaynabo Municipio

Guaynabo Municipio shares a land border with 4 county equivalents. It has more land than 1 of them. The largest neighbor is San Juan Municipio (47.9 mi²) and the smallest is Cataño Municipio (4.8 mi²). Together with its neighbors, Guaynabo Municipio forms a block of 154.8 mi² of land, of which it holds 17.8%.

How big is Guaynabo Municipio compared with U.S. states?

Guaynabo Municipio has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 38 times as much. Puerto Rico’s county land could hold about 124 areas the size of Guaynabo Municipio.

Another way to picture it: the same land area would fill a square about 5.25 miles (8.4 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 Guaynabo Municipio?

Guaynabo Municipio has more land than 48 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 Guaynabo Municipio at #3,188 nationally by total area, 14 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 0.7%, compared with a national county-equivalent median of 1.2% — 0.5 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 Guaynabo Municipio 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.