In 2023, Oso, WA had a population of 400 people with a median age of 25.9 and a median household income of $136,735. Between 2022 and 2023 the population of Oso, WA grew from 313 to 400, a 27.8% increase and its median household income declined from $153,482 to $136,735, a −10.9% decrease.
The 5 largest ethnic groups in Oso, WA are White (Non-Hispanic) (72.3%), Two Races Including Other (Hispanic) (27.8%), Black or African American (Non-Hispanic) (0%), American Indian & Alaska Native (Non-Hispanic) (0%), and Asian (Non-Hispanic) (0%).
None of the households in Oso, WA reported speaking a non-English language at home as their primary shared language. This does not consider the potential multi-lingual nature of households, but only the primary self-reported language spoken by all members of the household.
100% of the residents in Oso, WA are U.S. citizens.