Mill Creek, WA population, income and ZIP codes

Mill Creek city is a mid-size town in Washington, with 20,846 residents counted in the Census American Community Survey 2019-2023 ACS 5-year estimates, which places it #72 of 639 ranked by population — larger than 88% of them. The median age here is 38.8 years against 39.1 nationally, a slightly younger profile than the country as a whole. Places under 65,000 residents only appear in the five-year release, never the one-year file, so these values pool sixty months of responses and lag the current year by design.

Households in Mill Creek city earn a median of $121,578 a year, 54.8% above the national figure of $78,538 and 34% above the $90,592 median for the 393 Washington cities we cover. Median household income counts every pre-tax dollar arriving at an address — wages, self-employment, Social Security, pensions, interest and public assistance — for everyone living there, so multi-earner households pull the figure up even where individual pay is modest. Poverty reaches 4.9% of residents here, less than half the 12.4% national rate.

The typical owner-occupied home in Mill Creek city is valued at $836,300, 175.6% above the national figure and 79% above the $468,400 peer median, while median gross rent runs $2,197 a month, 56.3% above the national figure, or roughly $26,364 across a full year. A household on the local median income would put about 21.7% of gross pay toward that rent against the federal 30% cost-burden threshold, so renting here is within the standard affordability guideline. The home-price-to-income ratio works out to 6.9×, against roughly 3.9× nationally, so buying is out of reach on local earnings alone and the ownership market leans on outside income, equity or dual high earners. 59.8% of occupied homes are owner-occupied versus 65% nationally, so the market leans more heavily on renters. Gross rent folds in the utilities a tenant pays separately, so it is closer to the real monthly outlay than a headline rent figure.

Home values sit at 6.9× median household income, far past the 3.9× national mark, so ownership costs here are set by something other than local wages — second homes, retirees with equity, or commuters earning elsewhere.

No figure on this page is estimated by us; each one comes straight from the published ACS tables for this area. Small-area estimates still carry wider margins of error than state or national figures, so check the linked ACS tables before relying on them for lending, appraisal or legal work.