Which ZIP code in Montgomery County has the highest median age?

20818 (Cabin John), at 52.7 (±5.6), among 37 ZIP codes with at least 1,000 residents.

Why are some ZIP codes missing?

ZIP codes with fewer than 1,000 residents are left out because their survey estimates swing too much to rank, and so are ZIP codes where the Census Bureau did not publish this figure.

Oldest ZIP codes in Montgomery County, MD

These are the 25 ZIP codes in Montgomery County with the highest median age, out of 37 with at least 1,000 residents. 20818 (Cabin John, 52.7), 20861 (Ashton, 51.0) and 20860 (Sandy Spring, 49.6) lead the list. There is no single "best" ZIP code in Montgomery County; the right one depends on who you want to reach, so the same ZIP codes are ranked several ways below.

Oldest ZIP codes in Montgomery County

Rank	ZIP	Mailing city	Median age	Residents	Households	Residential mailboxes
1	20818	Cabin John	52.7 ±5.6	1,539	593	684
2	20861	Ashton	51.0 ±7.6	2,890	917	1,049
3	20860	Sandy Spring	49.6 ±13.4	2,035	735	886
4	20842	Dickerson	48.5 ±5.4	2,369	802	753
5	20854	Potomac	47.7 ±0.9	50,498	16,751	17,813
6	20841	Boyds	46.8 ±2.8	9,969	2,919	3,217
7	20882	Gaithersburg	46.6 ±1.1	13,751	4,693	4,737
8	20815	Chevy Chase	46.2 ±1.8	30,505	12,937	14,980
9	20837	Poolesville	45.9 ±10.0	6,699	2,366	2,359
10	20817	Bethesda	45.8 ±0.8	37,454	13,660	14,986
11	20833	Brookeville	45.2 ±4.5	7,860	2,568	2,686
12	20905	Silver Spring	44.8 ±1.1	19,004	5,899	5,788
13	20816	Bethesda	43.4 ±1.5	18,140	6,400	6,663
14	20895	Kensington	41.9 ±1.5	19,184	6,991	7,524
15	20853	Rockville	41.8 ±2.1	31,851	9,692	9,938
16	20878	Gaithersburg	41.4 ±0.9	66,115	24,237	25,897
17	20855	Derwood	41.3 ±1.5	17,279	6,437	6,958
18	20872	Damascus	41.3 ±3.1	13,983	4,659	4,948
19	20906	Silver Spring	41.2 ±1.3	70,595	25,958	27,180
20	20850	Rockville	41.2 ±1.3	50,353	21,159	23,039
21	20832	Olney	41.0 ±1.0	25,553	8,411	9,035
22	20904	Silver Spring	40.6 ±1.2	58,646	21,212	21,983
23	20814	Bethesda	39.9 ±2.3	32,795	14,904	18,961
24	20866	Burtonsville	39.9 ±2.5	15,986	5,033	5,051
25	20901	Silver Spring	39.5 ±1.3	36,435	13,114	13,058

How we ranked them

Ranked by median age of all residents, highest first (ACS 5-year estimates, 2020–2024). ZIP codes need at least 1,000 residents to be ranked; 37 of 48 qualify.

Which of these to mail, and why

Older ZIP codes respond to health care, hearing and vision, Medicare plans, home safety, estate planning and services that come to the door.

The top five ZIP codes on this list hold 19,798 households, on 63 carrier routes with 21,185 residential mailboxes. Open any of them on the route map to see each carrier route's own figures before you choose.

Open 20818 on the EDDM route map

More rankings

Businesses that mail these ZIP codes

Map it and price it

EDDM guides

Frequently asked questions

Which ZIP code in Montgomery County has the highest median age?: 20818 (Cabin John), at 52.7 (±5.6), among 37 ZIP codes with at least 1,000 residents.
How is this ranking calculated?: Ranked by median age of all residents, highest first (ACS 5-year estimates, 2020–2024).
Why are some ZIP codes missing?: ZIP codes with fewer than 1,000 residents are left out because their survey estimates swing too much to rank, and so are ZIP codes where the Census Bureau did not publish this figure.

This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.