San Diego County Demographics
If you’re looking to buy land in San Diego County, there are 4,206 square miles to choose from. Home to 3.3 million residents, the U.S. Census Report of 2020 shows it has a density of 735 residents per square mile.

As of 2020, San Diego County was the second-most populated county in the State of California, and it achieved the number five spot of the most populated states nationwide.

No surprise here, but the county seat is the City of San Diego, a sprawling metropolis that is one of the most populous cities in California, second only to the City of Los Angeles. San Diego is so big, that it rightfully earns its spot as the eighth-most populated city in the United States.

As the southwesternmost of the Lower 48, or the contiguous United States, San Diego County's southern boundary is the international border between the U.S. and Mexico. The county also belongs to the San Diego-Tijuana Transborder Metropolitan Area, a distinction that proves that just because borders stop, cultures do not. What this delineation effectively means is that the cities and population centers on each side of the border sprawl into one another.

On the western border of San Diego County, you’ll find over 50 miles of Pacific Ocean coastline. A strategic coastline at that, with San Diego County home to many military installations, mostly belonging to the United States Navy and the United States Marine Corps. You’ll find the following installations, but this is by no means an exhaustive list:

Marine Corps Air Station Miramar
Marine Corps Base Camp Pendleton
Marine Corps Recruit Depot San Diego
Naval Base Coronado
Naval Base Point Loma
Naval Base San Diego
U.S. Coast Guard Station San Diego

San Diego residents also find work in many other industries besides government, and the census reported that in 2020, San Diego County residents earned an average of $82,426 per year, an income that is slightly higher than the national average.

The other industries that San Diegans find work in, according to the City of San Diego are International trade, manufacturing, and tourism.

In 2014, Forbes called this southern California metropolis the Best Place to Launch a Startup, and in 2015 National Geographic ranked it as a World Smart City, the only North American city to achieve such an honor. The area has the number one concentration of military and defense assets in the world, according to the San Diego Military and Advisory Council, and the San Diego area is a leader in the Life and BioScience fields.