Washington, DC

ZIP code 20004 is assigned to Washington, DC, and falls within District of Columbia County. Like every US postal code, it began as a mail-routing device rather than a geographic boundary — the US Postal Service groups delivery routes under a single code so carriers and sorting equipment can process mail efficiently. Today it also serves as a practical shorthand for the area itself: roughly 1,756 people live inside it.

At 9,052 residents per square mile spread over 0.194 square miles, 20004 reads as a densely built-up area. It is a sparsely populated postal code, and density shapes almost everything else on this page — how people get to work, whether they own or rent, and what housing costs.

Household earnings here sit well above the national picture. The median household income of $161,359 places 20004 in the upper reaches of American postal codes, ahead of 98% of them. The US median for comparison is $70,109. Bear in mind that median income describes the midpoint household, not the average — it is not pulled upward by a handful of very high earners the way a mean would be.

Housing in 20004 costs far above the national median. A typical home is valued at $650,700 against a US median of $207,500, and median gross rent runs $2,945 a month. The split between owning and renting is fairly even at 40.8% owner-occupied, which tends to indicate a mix of housing types rather than one dominant form.

The building stock is dominated by larger apartment buildings of twenty units or more, which account for 83.3% of housing units here. The median construction year is 1995, making the housing here from the later twentieth century. The vacancy rate of 21.5% is high, which in many places reflects seasonal or second-home use rather than abandonment.

The population skews broadly in line with the national age profile, with a median age of 42.4 against 42 nationally. Households average just 1.4 people, and 61.5% consist of one person living alone — a signature of areas with a lot of studio and one-bedroom stock.

Getting to work takes 25.2 minutes on average one way. The dominant mode is walked at 40.3% of workers, while 21.4% take public transit, 40.3% walk, 24.2% work from home. Commute patterns are one of the better proxies for how a place actually functions day to day.

Beyond addressing mail, 20004 does a lot of quiet administrative work. Retailers use it to calculate shipping and sales tax at checkout. Insurers use it to set premiums, since risk profiles vary geographically. Employers and marketers use it to define service areas. Government agencies use it to route benefits and organise reporting. If you have ever been asked for a postal code by a form that clearly does not intend to send you anything, this is why.

For anyone weighing a move, 20004 offers a compact profile of Washington: 1,756 residents, a median household income of $161,359, 94.9% of adults holding a bachelor's degree or higher, and an unemployment rate of 1.8%. A handful of figures like these answer more relocation questions than most neighbourhood guides do.

One caution worth repeating: a postal code is not a neighbourhood. 20004 may cover parts of several distinct areas, and a single neighbourhood in Washington may be split across more than one code. Boundaries also shift as USPS adjusts delivery routes. Treat the figures here as describing a delivery area, which is what they actually measure.