| City: | Cobb Island, Maryland |
| County: | Charles County |
| Timezone: | Eastern (GMT -05:00) |
| Local Time: | 9:55:07 PM |
| Population: | 848 [See All] |
| Area Codes: | 227 / 240 / 301 |
| Classification: | PO Box |
| Coordinates: | 38.2625, -76.8509 |
| Land Area: | 0.489 sq mi |
| Quick Link: |
Cobb Island sits where the Potomac and Wicomico Rivers meet in southern Maryland's Charles County. This waterfront community of 848 residents lives on an actual island, with water area (1.3 square miles) exceeding land (0.5 square miles). Street names tell the story: Neale Sound Drive, Potomac River Drive, Wicomico River Drive.
This is a PO Box Only Zone. There's no alternative mail delivery across the island's 1.9 square miles. The post office maintains 175 PO Boxes for 358 households, a 49% adoption rate that serves both year-round residents and seasonal homeowners. About 22% of homes (117 of 527 housing units) are used seasonally, making Cobb Island a mix of permanent residents and weekend retreaters.
The island supports both rural carrier routes (covering 74 delivery points) and a single city carrier route, reflecting its mix of waterfront properties and a small village center along Main Avenue. With only 11 business establishments employing 71 people, this isn't a commercial hub. It's a residential waterfront retreat.
Nearly half the workforce (48.6%) works from home, one of the highest remote work rates in Maryland. Median household income of $161,000 and median home values of $244,400 indicate an established professional population. Median age is 45.5 years. The population is 90% White, with 14% Hispanic or Latino.
Cobb Island has served as a recreational fishing destination since the late 19th century. The combination of waterfront access, proximity to Washington DC (about 50 miles south), and island character maintains its appeal as both a permanent residence and vacation retreat for those seeking river life.
All mail must be addressed to PO Boxes. The standard format:
Recipient Name
PO Box [Number]
Cobb Island, MD 20625General Delivery is available for temporary visitors at:
Recipient Name
General Delivery
Cobb Island, MD 20625Street names reference surrounding waterways: Neale Sound, Potomac River, and Wicomico River.
ZIP Code 20625 has 848 residents and 358 households (average 2.37 persons per household). The median age is 45.5 years, older than the state (38.8) and older than the nation (38.8). The gender split is 48.1% male and 51.9% female, which is about the same as the national male share (49.1%), making this a female-majority area. Largest groups are White (89.5%, much higher than the state average of 48.7% and well above the national average of 61.6%) and Black or African American (3.4%, much lower than the state average of 29.5% and well below the national average of 12.4%); Hispanic or Latino residents make up 1.9%, which is much lower than the national average (18.7%).
Explore More: Population Over Time By Age & Gender By Race By Gender Nativity & Citizenship
| 2020 Population: | 848Source: Census DHC |
| 2024 ACS Population Estimate: | 849Source: Census ACS |
| 2026 ZC Population Estimate: | 0Source: ZIP-Codes.com |
| Population Density: | 1,734.2 people per sq mile |
| Average Income: | $0Source: Census ACS |
| Households: | 358Source: Census DHC |
| Average House Value: | $245,300Source: Census ACS |
| Persons Per Household: | 2.37Source: Census DHC |
| Average Family Size: | 3.22Source: Census ACS |
| Group | 2010 | 2011 | 2102 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Census ACS Population Estimate | -- | 546 | 644 | 628 | 630 | 703 | 828 | 657 | 615 | 646 | 929 | 1,065 | 1,248 | 1,135 | 849 |
| Decennial Census | 1,062 | -- | -- | -- | -- | -- | -- | -- | -- | -- | 848 | -- | -- | -- | -- |
Median Age: 45.5
Male Median Age: 44.7
Female Median Age: 46
| Group | < 5 | 5-9 | 10-14 | 15-19 | 20-24 | 25-29 | 30-34 | 35-39 | 40-44 | 45-49 | 50-54 | 55-59 | 60-64 | 65-69 | 70-74 | 75-79 | 80-84 | 85+ |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Male | 22 | 25 | 11 | 14 | 31 | 27 | 28 | 21 | 26 | 31 | 27 | 37 | 26 | 17 | 31 | 15 | 10 | 9 |
| Female | 35 | 19 | 23 | 21 | 11 | 33 | 15 | 36 | 19 | 25 | 17 | 54 | 34 | 29 | 24 | 28 | 9 | 8 |
| Total | 57 | 44 | 34 | 35 | 42 | 60 | 43 | 57 | 45 | 56 | 44 | 91 | 60 | 46 | 55 | 43 | 19 | 17 |
| White: | 759 | 92.34% |
| Black: | 29 | 3.53% |
| Hispanic:* | 16 | 1.95% |
| Asian: | 9 | 1.09% |
| American Indian: | 0 | 0% |
| Hawaiian: | 0 | 0% |
| Other: | 9 | 1.09% |
| Total: | 822 | 100% |
| Gender | Count | % | Median Age |
|---|---|---|---|
| Males: | 408 | 48.11% | 44.7 years |
| Females: | 440 | 51.89% | 46.0 years |
| Total: | 848 | 100% | 45.5 years |
| Native, born in the United States: | 829 | 97.64% |
| Native, born in PR, Island Areas, or abroad: | 0 | 0.00% |
| Foreign born, naturalized U.S. citizen: | 0 | 0.00% |
| Foreign born, not a U.S. citizen: | 20 | 2.36% |
| Total Population: | 849 | 100% |
| Total Native Population: | 829 | 97.64% |
| Total Foreign-born Population: | 20 | 2.36% |
In 2024, the Median household income is $0, which is far less than the state median ($101,652), is down $58,996 (100.0%) since 2011 and below its 2019 pre-pandemic level by $95,417. Family households earn a median of $0 versus $0 for nonfamily households (a difference of $0). By gender, male median income is $0 and female is $45,750, which is well under the state female median ($68,044), with a current gap of $45,750 that has narrowed from 2011 to 2024. The labor-force participation rate is 67.9%, which is notably higher than the national rate (63.5%). The unemployment rate is 0.0%, which is markedly below the national rate (5.2%). The largest occupation group is Natural resources (33.5%).
Explore More: Income Over Time Household Income Employment Status By Occupation
| Income Type | 2011 | 2012 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Median Household Income | $58,996 | $59,010 | $62,440 | $61,818 | $71,094 | $0 | $0 | $0 | $95,417 | $0 | $115,491 | $126,657 | $161,000 | $0 |
| Median Family Income | $77,917 | $58,750 | $81,066 | $81,944 | $84,375 | $84,185 | $84,224 | $83,214 | $96,146 | $0 | $0 | $126,250 | $162,950 | $0 |
| Median NonFamily Income | $58,571 | $59,010 | $39,625 | $38,500 | $24,149 | $25,660 | $25,332 | $0 | $0 | $111,397 | $117,188 | $127,344 | $0 | $0 |
| Median Male Income | $59,408 | $58,718 | $72,796 | $69,844 | $0 | $75,379 | $78,578 | $96,823 | $57,237 | $47,277 | $58,513 | $63,611 | $66,283 | $0 |
| Median Female Income | $26,971 | $28,365 | $40,750 | $38,958 | $0 | $0 | $42,656 | $20,000 | $79,896 | $54,500 | $82,669 | $57,130 | $62,532 | $45,750 |
| Employed: | 469 | 67.87% |
| Unemployed: | 0 | 0.00% |
| Not In Labor Force: | 222 | 32.13% |
| Total: | 691 | 100% |
| Management, business, science, and arts: | 30 | 6.40% |
| Service: | 126 | 26.87% |
| Sales and Office: | 78 | 16.63% |
| Natural resources, construction, and maintenance: | 157 | 33.48% |
| Production, transportation, and material moving: | 78 | 16.63% |
| Total Civilian Employed Population: | 469 | 100% |
In 2024, the median home value is $245,300, which is considerably lower than the state median ($397,700), is down $12,700 (4.92%) since 2011 and below its 2019 pre-pandemic level by $85,800. The median gross rent is $0, which is far less than the state median ($1,662), is down $973 (100.00%) since 2011 and above its 2019 pre-pandemic level by $0. Of occupied housing, owners make up 100.00% (93.60% with a mortgage, 6.40% free-and-clear) and renters 0.00% - making this ZIP Code more home ownership than the state and under national rental averages. The vacancy rate is 36.31%, which is markedly above the state rate (8.09%).
Explore More: Compare Home Value Home Value Over Time Rent & Over Time Housing Occupancy
| Group | 2011 | 2102 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Median Home Value | $258,000 | $290,900 | $240,200 | $230,400 | $286,100 | $304,400 | $301,500 | $306,500 | $331,100 | $199,700 | $206,800 | $242,900 | $244,400 | $245,300 |
| Less than $500: | 0 | 0% |
| $500 to $999: | 0 | 0% |
| $1,000 to $1,499: | 0 | 0% |
| $1,500 to $1,999: | 0 | 0% |
| $2,000 to $2,499: | 0 | 0% |
| $2,500 to $2,999: | 0 | 0% |
| $3,000 or more: | 0 | 0% |
| No Rent: | 0 | 0% |
| Total: | 0 | 100% |
| Group | 2011 | 2102 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Median Rent | $973 | $1,023 | $1,583 | $1,232 | $1,163 | $1,375 | $0 | $0 | $0 | $0 | $0 | $0 | $0 | $0 |
| Owner Occupied (with mortgage): | 307 | 93.60% |
| Owner Occupied (free and clear, no mortgage): | 21 | 6.40% |
| Renter Occupied: | 0 | 0.00% |
| Total Occupied Housing Units: | 328 | 100% |
| Occupied Housing Units: | 328 | 63.69% |
| Vacant Housing Units (not graphed): | 187 | 36.31% |
| Total Housing Units: | 515 | 100% |
| Single-Family Units: | 515 | 100.00% |
| Multi-Family Units: | 0 | 0.00% |
| Other Units: | 0 | 0.00% |
| Total Housing Units: | 515 | 100% |
In 2024, 2.40% of adults (25+) have a bachelor's degree or higher, which is markedly below the state rate (42.70%). High school or higher is 95.10%, which is comparable to the national rate (89.40%). The uninsured rate is 2.40%, which is far lower than the national rate (8.60%). Private coverage is 92.90%, which is well above the national rate (67.30%). The share of people in poverty is 0.00%, which is comparable to the national rate (8.70%), down 7.10 percentage points since 2011. This points to a pronounced improvement in local conditions - rising incomes, firmer consumer demand, and a stronger tax base. Among residents ages 3+, the largest enrollment group is elementary (56.84%). College enrollment is 0.00%, which is markedly below the state rate (28.00%), indicating the community may be more oriented toward vocational/trade or direct-to-workforce opportunities.
Explore More: Educational Attainment Health Insurance Poverty Over Time School Enrollment
| Less than 9th grade: | 0 | 0.00% |
| 9th to 12th grade, no diploma: | 32 | 4.86% |
| High school graduate (includes equivalency): | 433 | 65.71% |
| Some college, no degree: | 148 | 22.46% |
| Associate's degree: | 30 | 4.55% |
| Bachelor's degree: | 0 | 0.00% |
| Graduate or professional degree: | 16 | 2.43% |
| Total: | 659 | 100% |
| High school or higher: | 627 | 95.14% |
| Bachelor's degree or higher: | 16 | 2.43% |
| Private Insurance: | 789 | 79.78% |
| Public Insurance: | 180 | 18.20% |
| No Insurance: | 20 | 2.02% |
| Total: | 989 | 100% |
| Has Health Insurance: | 969 | 97.98% |
| Group | 2011 | 2102 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| % of People in Poverty | 7.1% | 21.0% | 16.8% | 24.0% | 18.5% | 16.9% | 5.6% | 7.0% | 0.0% | 0.0% | 0.0% | 0.0% | 0.0% | 0.0% |
Note: Counts of Families & People in poverty are not published at the ZIP Code level due to small sample sizes. Percentages shown are survey estimates from the American Community Survey (ACS). They may differ from official poverty statistics. The U.S. Census Bureau defines poverty status by comparing a family's or individual's total income with federal poverty thresholds that vary by family size and composition.
| Nursery School, Preschool: | 0 | 0.00% |
| Kindergarten: | 0 | 0.00% |
| Elementary school (grades 1-8): | 108 | 56.84% |
| High school (grades 9-12): | 82 | 43.16% |
| College or graduate school: | 0 | 0.00% |
| Total: | 190 | 100% |
| Early Childhood: | 0 | 0.00% |
| K-12 (Primary & Secondary School): | 190 | 100.00% |
ZIP Code 20625 supports both business and residential activity. According to the Business Census (2024), there are 11 business establishments, employing about 75 people with an annual payroll of $2,481,000.
| # Residential Mailboxes: | 0Source: USPS |
| # Business Mailboxes: | 0Source: USPS |
| Total Delivery Receptacles: | 175Source: USPS |
| Single Family Delivery Units: | 0Source: USPS |
| Multi Family Delivery Units: | 0Source: USPS |
| # of Businesses: | 11Source: CBP |
| 1st Quarter Payroll: | $489,000Source: CBP |
| Annual Payroll: | $2,481,000Source: CBP |
| # of Employees: | 75Source: CBP |
ZIP Code 20625 is located in Charles County, Maryland, within the Washington-Arlington-Alexandria, DC-VA-MD-WV Metropolitan Statistical Area (CBSA 47900) and Maryland's 5th Congressional District. This Metro area has a population of 5,582,170 people, about 0.02% of whom live in ZIP Code 20625, and is subdivided into the Washington, DC-MD division. It covers 0.489 sq mi of land and a water area of 1.32 sq mi.
| CBSA Name: | Washington-Arlington-Alexandria, DC-VA-MD-WVSource: Census |
| CBSA Number: | 47900Source: Census |
| CBSA Type: | MetroSource: Census |
| CBSA Division: | Washington, DC-MD (CBSA Div 47764)Source: Census |
| CBSA Population: | 5,582,170Source: Census |
| MSA: | Washington-Baltimore, DC-MD-VA-WV CMSASource: Census |
| Land Area: | 0.489 sq miSource: Census |
| Water Area: | 1.32 sq miSource: Census |
| Congressional District: | 05Source: USPS |
| Congressional Land Area: | 1481.24 sq miSource: Census |
| PMSA: | Washington, DC-MD-VA-WV PMSASource: Census |
| Intro Date: | < 2004-10Source: ZIP-Codes.com |
| Place FIPS Code: | 2418200Source: Census |
| Place Name: | Cobb Island CDP; MarylandSource: Census |
We could not locate which school district 20625 belongs to, but we will update this once new district data is released. There are no public schools nor private schools with a mailing address in this ZIP Code. Listing Nearby schools instead. It also has 6 colleges, universities or post secondary education institutions nearby which would be a short commute to.
Our sources include trusted federal and licensed data from the United States Postal Service, U.S. Census Bureau, U.S. Geological Survey, Centers for Medicare & Medicaid Services, and the National Center for Education Statistics, along with proprietary datasets created by ZIP-Codes.com. Data last updated on February 1, 2026.