Monongahela is a very small city located in the state of Pennsylvania. With a population of 4,108 people and four associated neighborhoods, Monongahela is the 376th largest community in Pennsylvania. Monongahela has an unusually large stock of pre-World War II architecture, making it one of the older and more historic cities.

Telecommuters are a relatively large percentage of the workforce: 7.31% of people work from home. While this number may seem small overall, as a fraction of the total workforce it is high relative to the nation. These workers are often telecommuters who work in knowledge-based, white-collar professions. For example, Silicon Valley has large numbers of people who telecommute. Other at-home workers may be self-employed people who operate small businesses out of their homes.

In terms of college education, Monongahela is nearly on par with the US average for all cities of 21.84%: 19.57% of adults 25 and older in Monongahela have a bachelor's degree or advanced degree.

The per capita income in Monongahela in 2018 was $30,490, which is lower middle income relative to Pennsylvania, and middle income relative to the rest of the US. This equates to an annual income of $121,960 for a family of four. However, Monongahela contains both very wealthy and poor people as well.

The people who call Monongahela home describe themselves as belonging to a variety of racial and ethnic groups. The greatest number of Monongahela residents report their race to be White, followed by Black or African-American. Important ancestries of people in Monongahela include German, Italian, Irish, English, and Polish.

The most common language spoken in Monongahela is English. Other important languages spoken here include Slavic languages and Spanish.