ZIP code 57631

ZIP 57631 is a very small community in Walworth County, South Dakota, with 365 residents counted in the Census American Community Survey 2019-2023 ACS 5-year estimates, which places it #244 of 375 ranked by population — larger than 35% of them. The median age here is 60.5 years against 39.1 nationally, a markedly older profile that usually tracks retirees staying put and younger households leaving for work. At this population the ACS sample is small, so the margin of error around every dollar figure below is wide — treat the numbers as a band, not a point, and expect them to move between annual releases without the place itself changing.

Households in ZIP 57631 earn a median of $56,250 a year, 28.4% below the national figure of $78,538. 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 4.4% of residents here, less than half the 12.4% national rate.

The typical owner-occupied home in ZIP 57631 is valued at $106,700, 64.8% below the national figure, while median gross rent runs not published a month. The home-price-to-income ratio works out to 1.9×, against roughly 3.9× nationally, so purchase prices are unusually low against local pay, the pattern in places where supply is plentiful and wage growth has been flat. 90.4% of occupied homes are owner-occupied versus 65% nationally, an owner-dominated market where rental listings are scarce and rent medians rest on a thin sample. Rent is reported gross — contract rent plus tenant-paid utilities — which is why it runs above the advertised price on a listing for the same unit.

A median age of 60.5 puts ZIP 57631 well into retirement-weighted territory, which pulls median household income down even where household wealth is high, because retirement draws are counted differently from wages. With 365 residents, a handful of survey responses moves every median on this page. Compare ZIP 57631 against its county rather than against national figures.

The Census withheld gross rent for ZIP 57631 because the sample was too thin to publish at this geography. Those values were suppressed at the source, not lost in our dataset, and we do not model a replacement. Everything else on this page comes straight from the ACS 2019-2023 ACS 5-year tables.

ZIP 57631 is tabulated inside Walworth County, South Dakota, one of 4 ZIP areas the Census publishes for that county and 375 across South Dakota. This is one of the smallest tabulated ZIP areas in the state, the kind of rural route where a single subdivision or farm cluster accounts for most addresses. County assignment on this page follows the largest share of the ZIP's land area, which matters where a delivery route crosses a county line: mail addressed to 57631 can be handled by a post office in a neighbouring county even though the tabulation area is filed here.

Against its own county, 57631 reports a median household income of $56,250, close to the $55,000 county median, and 21% below the $71,607 typical SD ZIP. Owner-occupied homes are valued at a median of $106,700, 14% above the county figure and 34% below the statewide ZIP median. Rent is reported gross — the contract amount plus tenant-paid utilities — at not published a month, which is why it reads higher than the advertised rent on a listing for the same unit.

South Dakota charges 4.2% statewide, and local governments overlapping 57631 may add county, city or special-district levies on top. We publish the state floor for this ZIP rather than guessing a combined figure, because ZIP boundaries and taxing-district boundaries were drawn for different purposes and do not line up.

Everything above comes from the Census Bureau American Community Survey 2019-2023 ACS 5-year estimates for this ZIP Code Tabulation Area, with sales tax rates traced to the state revenue agency. Five-year estimates pool sixty months of responses, so they are stable enough to compare 57631 with its neighbours but always trail the current year, and any value the Census suppressed for sample size is shown as unpublished rather than filled in with a model.