Which ZIP code in St. Mary's County has the lowest median age?

20670 (Patuxent River), at 22.9 (±1.5), among 11 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.

Youngest ZIP codes in St. Mary's County, MD

These are the 11 ZIP codes in St. Mary's County with the lowest median age, out of 11 with at least 1,000 residents. 20670 (Patuxent River, 22.9), 20634 (Great Mills, 32.0) and 20653 (Lexington Park, 34.8) lead the list. There is no single "best" ZIP code in St. Mary's County; the right one depends on who you want to reach, so the same ZIP codes are ranked several ways below.

Youngest ZIP codes in St. Mary's County

Rank	ZIP	Mailing city	Median age	Residents	Households	Residential mailboxes
1	20670	Patuxent River	22.9 ±1.5	2,046	439	582
2	20634	Great Mills	32.0 ±4.0	7,088	2,694	2,820
3	20653	Lexington Park	34.8 ±1.5	26,852	11,028	10,223
4	20619	California	36.6 ±2.5	14,212	5,719	6,282
5	20659	Mechanicsville	37.5 ±1.7	24,324	8,300	8,521
6	20650	Leonardtown	38.6 ±1.4	16,094	5,642	5,712
7	20636	Hollywood	39.4 ±4.3	10,486	3,324	4,096
8	20620	Callaway	41.6 ±7.9	1,115	389	476
9	20690	Tall Timbers	45.7 ±17.8	1,077	478	361
10	20622	Charlotte Hall	49.4 ±7.0	5,185	1,489	1,585
11	20618	Bushwood	52.0 ±4.9	1,705	656	315

How we ranked them

Ranked by median age of all residents, lowest first (ACS 5-year estimates, 2020–2024). ZIP codes need at least 1,000 residents to be ranked; 11 of 27 qualify.

Which of these to mail, and why

Younger ZIP codes skew toward renters, students and young families: fitness, quick-service food, apartments, entertainment and first-time-buyer offers.

The top five ZIP codes on this list hold 28,180 households, on 46 carrier routes with 28,428 residential mailboxes. Open any of them on the route map to see each carrier route's own figures before you choose.

Open 20670 on the EDDM route map

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Businesses that mail these ZIP codes

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Frequently asked questions

Which ZIP code in St. Mary's County has the lowest median age?: 20670 (Patuxent River), at 22.9 (±1.5), among 11 ZIP codes with at least 1,000 residents.
How is this ranking calculated?: Ranked by median age of all residents, lowest 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.