ZIP codes
26
St. Mary's County, MD Demographics & ZIP Codes
St. Mary's County, Maryland demographics and median household income by ZIP code — 26 ZIP codes — population 112,761 — avg. income $122,516 — avg. home value $441,255. Compare income, housing, and ZIP-level data on US5.
Population
112,761
Median household income (avg.)
$122,516
163% of U.S. median
Average home value
$441,255
127% of U.S. median
Average rent
$1,417
122% of U.S. median
St. Mary's County demographics
St. Mary's County, Maryland covers 26 ZIP codes, with a combined ZIP-area population of about 112,761.
Median household income in St. Mary's County
The average median household income across ZIP codes in St. Mary's County, Maryland is about $122,516 — about 10% above the MD ZIP average ($111,660), and about 63% above the U.S. median ($75,149).
Among ZIPs with income data, 20630 is near the top at about $227,581, while 20626 is near the bottom at about $53,143.
Housing in St. Mary's County
For housing in St. Mary's County, Maryland, the average median home value is about $441,255 and the average median rent is about $1,417.
The most populous ZIP is 20653 (Lexington Park) with about 26,799 residents. Use the table below to compare ZIP codes across the county.
ZIP codes in St. Mary's County
Sort by population, income, or home value. Click a column header to toggle ascending / descending.
| ZIP | City | County | State | Population ↓ | Income | Home value |
|---|---|---|---|---|---|---|
| 20653 | Lexington Park | St. Mary's County | MD | 26,799 | $97,923 | $341,900 |
| 20659 | Mechanicsville | St. Mary's County | MD | 23,918 | $117,571 | $388,400 |
| 20650 | Leonardtown | St. Mary's County | MD | 15,979 | $139,688 | $464,000 |
| 20619 | California | St. Mary's County | MD | 14,743 | $114,848 | $364,200 |
| 20636 | — | St. Mary's County | MD | 10,357 | $159,800 | $470,300 |
| 20634 | California | St. Mary's County | MD | 6,976 | $117,431 | $334,800 |
| 20670 | — | St. Mary's County | MD | 1,577 | $70,945 | — |
| 20618 | — | St. Mary's County | MD | 1,513 | $103,115 | $291,900 |
| 20620 | Callaway | St. Mary's County | MD | 1,160 | $154,188 | $369,200 |
| 20624 | — | St. Mary's County | MD | 1,157 | $99,638 | $423,700 |
| 20690 | Tall Timbers | St. Mary's County | MD | 1,046 | $129,236 | $558,900 |
| 20609 | — | St. Mary's County | MD | 976 | $114,181 | $474,700 |
| 20686 | — | St. Mary's County | MD | 949 | — | — |
| 20621 | — | St. Mary's County | MD | 902 | — | $562,500 |
| 20684 | — | St. Mary's County | MD | 825 | $176,938 | $375,500 |
| 20628 | — | St. Mary's County | MD | 791 | $160,043 | $412,100 |
| 20680 | — | St. Mary's County | MD | 702 | $81,125 | $392,400 |
| 20674 | Piney Point | St. Mary's County | MD | 638 | $126,029 | $398,600 |
| 20692 | Tall Timbers | St. Mary's County | MD | 438 | $120,491 | $381,700 |
| 20630 | — | St. Mary's County | MD | 346 | $227,581 | $584,600 |
| 20687 | — | St. Mary's County | MD | 331 | — | $771,600 |
| 20606 | — | St. Mary's County | MD | 204 | $86,406 | $464,100 |
| 20626 | — | St. Mary's County | MD | 198 | $53,143 | — |
| 20656 | — | St. Mary's County | MD | 122 | — | — |
| 20667 | — | St. Mary's County | MD | 98 | — | — |
| 20660 | — | St. Mary's County | MD | 16 | — | — |
Frequently asked questions
What are the demographics of St. Mary's County?
St. Mary's County, Maryland has a combined ZIP-area population of about 112,761 across 26 ZIP codes. Browse the ZIP table for population, income, and housing by code.
What is the median household income in St. Mary's County?
The average median household income across ZIP codes in St. Mary's County, Maryland is about $122,516, about 10% above the state ZIP average ($111,660), and about 63% above the U.S. median ($75,149). Average median home value is about $441,255. Among ZIPs with data, 20630 is near the top ($227,581) and 20626 is near the bottom ($53,143).
How many ZIP codes are in St. Mary's County?
St. Mary's County, Maryland includes 26 ZIP codes on US5. Each row links to demographics, median income, and housing for that code.
Where can I find ZIP code demographics for St. Mary's County?
This page lists ZIP codes in St. Mary's County, Maryland with population, median household income, and home value. Select a ZIP for a full demographics profile.