ZIP code 20618

ZIP 20618 is a small town in St. Mary's County, Maryland, with 1,513 residents counted in the Census American Community Survey 2019-2023 ACS 5-year estimates, which places it #328 of 477 ranked by population — larger than 31% of them. The median age here is 51.4 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 20618 earn a median of $103,115 a year, 31.3% above the national figure of $78,538. 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 3.5% of residents here, less than half the 12.4% national rate.

The typical owner-occupied home in ZIP 20618 is valued at $291,900, 3.8% below the national figure, while median gross rent runs $1,606 a month, 14.2% above the national figure, or roughly $19,272 across a full year. A household on the local median income would put about 18.7% of gross pay toward that rent against the federal 30% cost-burden threshold, so renting here is cheap relative to what people here earn. The home-price-to-income ratio works out to 2.8×, against roughly 3.9× nationally, so buying is easier here than in the average US market. 82.1% 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. The rent line includes utilities paid by the tenant, a definition worth remembering when comparing it against a landlord's quoted rate.

A median age of 51.4 puts ZIP 20618 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.

Every value on this page is published directly by the Census for this area — nothing is modelled or interpolated. 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.

ZIP 20618 is tabulated inside St. Mary's County, Maryland, one of 26 ZIP areas the Census publishes for that county and 477 across Maryland. Fewer than 2,500 people are counted here, so the ZIP behaves like a village delivery route rather than a neighbourhood. 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 20618 can be handled by a post office in a neighbouring county even though the tabulation area is filed here.

Against its own county, 20618 reports a median household income of $103,115, 12% below the $117,501 county median, and close to the $104,338 typical MD ZIP. Owner-occupied homes are valued at a median of $291,900, 28% below the county figure and 27% below the statewide ZIP median. Rent is reported gross — the contract amount plus tenant-paid utilities — at $1,606 a month, which is why it reads higher than the advertised rent on a listing for the same unit.

Maryland charges 6% statewide, and no local sales tax is layered on top, so the state rate is the full amount collected in 20618.

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 20618 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.