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zipcodes.pro — STATE/MD/COUNTY/ST-MARY-S

St. Mary's County, MD ZIP codes

There are 28 ZIP codes in St. Mary's County, MD, in 28 towns, from 20606 to 20692. The largest are 20659 (Mechanicsville), 20653 (Lexington Park) and 20619 (California).

The county seat is Leonardtown.

ZIP codes
28
Towns
28
County seat
Leonardtown
County FIPS
24037
Population
115,126
Median household income
$119,446
Land area
359 sq mi
Area codes
227, 240, 301
Metro area
Lexington Park

St. Mary's County ZIP codes by town

Leonardtown (county seat)
20650

Each ZIP code is listed under the county most of its land lies in and the town the Postal Service names it for; a ZIP code's own page shows exactly how it is split.

Map of St. Mary's County ZIP codes

20606206092061820619206202062120624206262062720628206302063420635206362065020653206562065920660206672067020674206802068420686206872069020692

The ZIP codes of St. Mary's County, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.

St. Mary's County in numbers

About 115,126 people live in St. Mary's County, in 42,436 households, the 12th most populous of Maryland's 24 counties. The median household income is $119,446 a year, 15% above the Maryland median of $103,678 (US: $80,734). The median owner-occupied home is valued at $407,600 (about the same as the Maryland median), and median gross rent is $1,747 a month. The median age is 37.2; 36.5% of adults 25 and over hold a bachelor's degree or higher (43.4% across Maryland); the average commute takes 30 minutes.

Population115,126St. Mary's115,126
Households42,436St. Mary's42,436
Median age37.2St. Mary's37.2Maryland39.4US 38.9
Median household income$119,446St. Mary's$119,446Maryland$103,678US $80,734
Median home value$407,600St. Mary's$407,600Maryland$419,900US $332,700
Median gross rent$1,747St. Mary's$1,747Maryland$1,705US $1,413
Bachelor's degree or higher36.5%St. Mary's36.5%Maryland43.4%US 35.7%
Mean commute29.9 minSt. Mary's29.9 minMaryland31.1 minUS 26.4 min
Population density321 / sq miSt. Mary's321 / sq mi

U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates. Survey estimates carry margins of error, wider for small places. Sources and methods.

Largest towns in St. Mary's County

Largest towns in St. Mary's County
TownZIP codesPopulation
Lexington Park 1 13,252
California 1 13,136
Hollywood 1 10,486
Great Mills 1 7,088
Leonardtown 1 4,808
Patuxent River 1 2,046
Bushwood 1 1,705
Mechanicsville 1 1,395
Piney Point 1 1,274
Saint Marys City 1 971
Chaptico 1 958
Callaway 1 930
Saint Inigoes 1 802
Clements 1 796
Avenue 1 714

Population of the census place of that name where there is one, otherwise of the ZIP codes the Postal Service addresses by it. A town's ZIP codes can reach past the county line.

Neighbouring counties

Counties that share a ZIP code with St. Mary's County.

Not sure you are in St. Mary's County? What county am I in? answers from your location, near a county line included.

Every ZIP code in St. Mary's County, with figures

ZIP codes in St. Mary's County
ZIP City Type Population Median income Median home
20606 Abell , MD Standard 291 $88,262 $451,000
20609 Avenue , MD Standard 714 $118,102 $568,400
20618 Bushwood , MD Standard 1,705 $105,508 $355,000
20619 California , MD Standard 14,212 $119,432 $376,800
20620 Callaway , MD Standard 1,115 $165,972 $391,300
20621 Chaptico , MD Standard 958 — $481,100
20624 Clements , MD Standard 796 $104,545 $430,600
20626 Coltons Point , MD Standard 284 — —
20627 Compton , MD No street area — — —
20628 Dameron , MD Standard 503 — $545,800
20630 Drayden , MD Standard 559 $233,411 $618,100
20634 Great Mills , MD Standard 7,088 $139,375 $342,300
20635 Helen , MD No street area — — —
20636 Hollywood , MD Standard 10,486 $163,690 $474,000
20650 Leonardtown , MD Standard 16,094 $143,116 $481,700
20653 Lexington Park , MD Standard 26,852 $103,048 $353,300
20656 Loveville , MD Standard 87 — —
20659 Mechanicsville , MD Standard 24,324 $121,654 $416,900
20660 Morganza , MD Standard 14 — —
20667 Park Hall , MD Standard 150 — —
20670 Patuxent River , MD Standard 2,046 $70,371 —
20674 Piney Point , MD Standard 769 $171,985 $592,400
20680 Ridge , MD Standard 663 — $397,500
20684 Saint Inigoes , MD Standard 802 $180,060 $360,500
20686 Saint Marys City , MD Standard 971 — —
20687 Scotland , MD Standard 415 — $458,100
20690 Tall Timbers , MD Standard 1,077 $122,750 $379,700
20692 Valley Lee , MD Standard 505 $201,250 $468,000

Cite this page

zipcodes.pro. “St. Mary's County ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/md/county/st-mary-s

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