Monongahela is a very small city located in the state of Pennsylvania. With a population of 4,087 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.

Also of interest is that Monongahela has more people living here who work in computers and math than 95% of the places in the US.

A relatively large number of people in Monongahela telecommute to their jobs. Overall, about 8.38% of the workforce works from home. While this may seem like a small number, as a fraction of the total workforce it ranks among the highest in the country. 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.

The population of Monongahela overall has a level of education that is slightly above the US average for all US cities and towns of 21.84%. Of adults 25 and older in Monongahela, 21.08% have at least a bachelor's degree.

The per capita income in Monongahela in 2022 was $33,624, which is middle income relative to Pennsylvania and the nation. This equates to an annual income of $134,496 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, Irish, Italian, English, and Polish.

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