Louisville, KY

ZIP code 40209 is assigned to Louisville, KY, and falls within Jefferson 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 571 people live inside it.

At 132 residents per square mile spread over 4.325 square miles, 40209 reads as a rural 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 run below the national median. At $52,697, 40209 sits in the lower half, ahead of 20% 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 40209 costs below the national median. A typical home is valued at $128,200 against a US median of $207,500, and median gross rent runs $1,083 a month. The split between owning and renting is fairly even at 52.4% owner-occupied, which tends to indicate a mix of housing types rather than one dominant form.

The building stock is dominated by detached single-family houses, which account for 100.0% of housing units here. The median construction year is 1953, making the housing here mid-century.

The population skews broadly in line with the national age profile, with a median age of 39 against 42 nationally. Households average just 1.93 people, and 38.2% consist of one person living alone — a signature of areas with a lot of studio and one-bedroom stock.

Getting to work takes 18.5 minutes on average one way. The dominant mode is drove alone at 55.5% of workers.

Beyond addressing mail, 40209 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, 40209 offers a compact profile of Louisville: 571 residents, a median household income of $52,697, 5.6% of adults holding a bachelor's degree or higher, and an unemployment rate of 10.5%. 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. 40209 may cover parts of several distinct areas, and a single neighbourhood in Louisville 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.