St. Marks, FL population, income and ZIP codes

St. Marks city is a very small community in Florida, with 273 residents counted in the Census American Community Survey 2019-2023 ACS 5-year estimates, which places it #897 of 955 ranked by population — larger than 6% of them. The median age here is 60.8 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 St. Marks city earn a median of $57,083 a year, 27.3% below the national figure of $78,538 and 17% below the $68,617 median for the 775 Florida cities we cover. The median is the midpoint household, not an average, so a handful of very high earners cannot drag it upward the way they distort a mean. Poverty reaches 12.5% of residents here, above the 12.4% national rate.

The typical owner-occupied home in St. Marks city is valued at $270,800, 10.7% below the national figure and 11% below the $305,300 peer median, while median gross rent runs $980 a month, 30.3% below the national figure, or roughly $11,760 across a full year. A household on the local median income would put about 20.6% 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 4.7×, against roughly 3.9× nationally, so buying is harder here than in the average US market. 79.6% of occupied homes are owner-occupied versus 65% nationally, so the market leans toward owners. 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 60.8 puts St. Marks city 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 273 residents, a handful of survey responses moves every median on this page. Compare St. Marks city against its county rather than against national figures.

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.