Arlington is a medium-sized city located in the state of Washington. With a population of 21,059 people and nine associated neighborhoods, Arlington is the 60th largest community in Washington.

Housing costs in Arlington are among some of the highest in the nation, although real estate prices here don't compare to real estate prices in the most expensive communities in Washington.

Telecommuters are a relatively large percentage of the workforce: 11.47% 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.

The citizens of Arlington are slightly better educated than the national average of 21.84% for all cities and towns, with 21.54% of adults in Arlington having a bachelor's degree or advanced degree.

The per capita income in Arlington in 2022 was $43,785, which is upper middle income relative to Washington and the nation. This equates to an annual income of $175,140 for a family of four. However, Arlington contains both very wealthy and poor people as well.

Arlington is a very ethnically-diverse city. The people who call Arlington home describe themselves as belonging to a variety of racial and ethnic groups. The greatest number of Arlington residents report their race to be White, followed by Asian. Arlington also has a sizeable Hispanic population (people of Hispanic origin can be of any race). People of Hispanic or Latino origin account for 14.60% of the city’s residents. Important ancestries of people in Arlington include German, English, Irish, Norwegian, and Scottish.

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