The size of a police department depends on many variables.
The size of a police department depends on many variables.

Police departments in the United States vary greatly in size. Usually, the larger a city is, the bigger its police force becomes. Small towns tend to have small police departments, but there are exceptions. If the crime rate in a town with a small population is high, the police force often will be larger to combat it.

Urban

Cities usually require a large police force to combat increased crime.
Cities usually require a large police force to combat increased crime.

Urban police departments are usually much larger than rural police departments because of the population density of the area and the higher rate of crime. New York City has the largest police force in the United States with just under 40,000 sworn-in officers, according to the Huffington Post. Those numbers will soon dwindle due to budget cuts, the Post reports.

Rural

Some areas and towns are so small that they don't employ a police force at all. They depend on the state to provide police coverage in the unlikely event that there is a crime. State police officers will also patrol these areas to check on traffic violations.

Nationwide

It is common to see a police department comprised of fewer than 25 officers. In fact, the CBS Interactive Business Network reports that 87 percent of all police departments in the United States have just a few dozen officers in their force. Most small cities and towns do not need the extensive manpower that large cities require and have no trouble employing just a few officers.