ZIP codes

ZIP codes in Montgomery County, Maryland

Montgomery County has 53 ZIP codes. 42 lie entirely inside it and 11 are shared with neighboring counties, so part of their land and their people are elsewhere. About 1,067,863 people live in the parts inside it (ACS 2020–2024).

By the All Map Tools Team

ZIP codes: 53; With 1% or more of their land inside
Entirely inside: 42; 99% or more of their land
Shared with other counties: 11; Most with Prince George's County (5)
Most populated ZIP: 20906; 70,595 people · Aspen Hill
Least populated ZIP: 20899; 57 people · Gaithersburg; 2 more with nobody living there
Largest ZIP by land: 20842; 56 sq mi

Map of the ZIP codes in Montgomery County

Entirely in the county (99% or more of its land)
Shared, mostly in this county
Shared, mostly in other counties
Neighboring counties

Open in the interactive tool

Each area is a ZIP code with its number where it fits. Hover over one to see its name.

All ZIP codes in Montgomery County

53 ZIP codes in Montgomery County, MD, by number
ZIP code	Main city	Population	Land in the county	Residents in the county
20705	Beltsville	28,713	1.1%	≈ 388
20707	Laurel	37,278	6.2%	≈ 1,321
20777	Highland	3,221	1.7%	≈ 70
20812	Glen Echo	276	100%	276
20814	Bethesda	32,795	100%	32,795
20815	Chevy Chase	30,505	100%	30,505
20816	Bethesda	18,140	100%	18,140
20817	Bethesda	37,454	100%	37,454
20818	Cabin John	1,539	100%	1,539
20832	Olney	25,553	100%	25,553
20833	Olney	7,860	90%	≈ 7,284
20837	Poolesville	6,699	100%	6,699
20838	Barnesville	306	100%	306
20839	—	158	100%	158
20841	Ten Mile Creek	9,969	100%	9,969
20842	—	2,369	77%	≈ 1,792
20850	Rockville	50,353	100%	50,353
20851	Rockville	14,946	100%	14,946
20852	North Bethesda	48,180	100%	48,180
20853	Aspen Hill	31,851	100%	31,851
20854	Potomac	50,498	100%	50,498
20855	Redland	17,279	100%	17,279
20860	Ashton-Sandy Spring	2,035	100%	2,035
20861	Ashton-Sandy Spring	2,890	100%	2,890
20862	Ashton-Sandy Spring	430	100%	430
20866	Burtonsville	15,986	100%	15,986
20868	Burtonsville	198	100%	198
20871	Clarksburg	30,182	94%	≈ 28,754
20872	Damascus	13,983	100%	13,983
20874	Darnestown	62,738	100%	62,738
20876	Germantown	26,406	100%	26,406
20877	Gaithersburg	38,546	100%	38,546
20878	Gaithersburg	66,115	100%	66,115
20879	Flower Hill	25,264	100%	25,264
20880	Washington Grove	577	100%	577
20882	Damascus	13,751	100%	13,751
20886	Montgomery Village	34,718	100%	34,718
20889	Bethesda	584	100%	584
20892	Bethesda	0	100%	0
20894	Bethesda	0	100%	0
20895	South Kensington	19,184	100%	19,184
20896	Garrett Park	932	100%	932
20899	Gaithersburg	57	100%	57
20901	Silver Spring	36,435	100%	36,435
20902	Wheaton	54,261	100%	54,261
20903	Hillandale	24,815	95%	≈ 21,831
20904	Colesville	58,646	98%	≈ 55,735
20905	Cloverly	19,004	100%	19,004
20906	Aspen Hill	70,595	100%	70,595
20910	Silver Spring	45,943	100%	45,943
20912	Takoma Park	25,749	90%	≈ 22,831
21771	Green Valley	33,031	4.2%	≈ 639
21797	Lisbon	8,643	1.3%	≈ 85

ZIP codes shared with other counties

These 11 ZIP codes have part of their land in another county. The first figure is the share of their land in Montgomery County; then, where the rest lies.

20705 (Beltsville): 1.1% here; 99% in Prince George's County.
20707 (Laurel): 6.2% here; 94% in Prince George's County.
20777 (Highland): 1.7% here; 98% in Howard County.
20833 (Olney): 90% here; 9.8% in Howard County.
20842: 77% here; 23% in Frederick County.
20871 (Clarksburg): 94% here; 5.6% in Frederick County.
20903 (Hillandale): 95% here; 4.9% in Prince George's County.
20904 (Colesville): 98% here; 2.5% in Prince George's County.
20912 (Takoma Park): 90% here; 10% in Prince George's County.
21771 (Green Valley): 4.2% here; 51% in Frederick County, 26% in Carroll County, and 18% in Howard County.
21797 (Lisbon): 1.3% here; 67% in Howard County and 32% in Carroll County.

Cities and prefixes

By main city (the city, town or CDP each ZIP shares the most land with), the ones with the most are Bethesda (6), Ashton-Sandy Spring (3), Gaithersburg (3), Aspen Hill (2), Burtonsville (2), and Damascus (2); 36 places in all.

They start with 4 different three-digit prefixes, one per USPS sorting center: 207, 208, 209, and 217.

Neighboring counties

Each one with its ZIP codes. Those without a page of their own open in the tool.

Tools for this county

ZIP codes by county or city The same ZIP codes on an interactive map, with the list as CSV or to copy County map with cities Its cities, towns and CDPs with their population ZIP codes in a radius The ZIP codes within 10 miles of its center, or any distance you like

Sources

U.S. Census Bureau, 2020 ZCTA to County, ZCTA to Place and ZCTA to Census Tract Relationship Files (and the 2022 County Subdivision to ZCTA file for Connecticut). Public domain.
U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates, table B01003 (population of each ZIP code, census tract and Connecticut town). Public domain.
U.S. Census Bureau, Vintage 2025 Population Estimates (county population) and 2025 Gazetteer Files (land area and interior point of each ZIP code). Public domain.
U.S. Census Bureau, Cartographic Boundary Files: ZCTAs 2020 and counties 2025, 1:500,000; county adjacency file 2025. Public domain.

How we count. ZIP codes here are the Census Bureau’s ZIP Code Tabulation Areas (ZCTAs), the areas it draws to match USPS ZIP codes; ZIPs with no area of their own (PO boxes, single buildings) aren’t included. A ZIP can cross county lines: “Land in the county” is the exact share of its land inside, from the Census relationship files. “Residents in the county” is the whole ZIP for those entirely inside; for shared ones it’s an estimate, spreading the people of each census tract over the land it shares with the ZIP. Population: ACS 2020–2024. Methodology.

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