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zipcodes.pro — ZIP/20659

20659

ZIP 20659 is Mechanicsville, Maryland, mostly in St. Mary's County; area codes 240, 301 and 227; Eastern time.

Type
Standard
Time zone
America/New_York
County
St. Mary's +1 more
Metro area
Lexington Park, MD
Population
24,324
Coordinates
38.4079, -76.7320
☼ Live from 20659 — Mechanicsville, MD

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Where 20659 is

Approximate ZIP boundary (Census ZCTA 2020). ZIP codes are mail routes, not areas, so the shape shown is the Census tabulation area that approximates it.

★ Weird and wonderful facts about 20659
  • 🔢 Type 20659 into a pocket calculator and turn it upside down: GSgOZ — not quite a word, sorry.
  • ➕ As a number, 20,659 = 73 × 283. Its digits add up to 22, a total 2,607 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101000010110011
  • 🏠 Its numerical neighbours: 20658 (Marbury, MD, 26 mi away) and 20660 (Morganza, MD, 3 mi away).
  • 🔄 Backwards, 20659 becomes 95602 — and that is a real ZIP code: Auburn, CA, 2,369 miles away.
  • 👥 48 other ZIP codes are made of exactly the same digits (02659, 06259, 09265, 09625, 20695, 25690, …). The farthest-flung twin is 96520 in APO AA, a military post office, 10,201 miles away.
  • 🧭 Farther south than 55% of all ZIP codes, and farther east than 83%.
  • 🎯1,172 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 20659 and you would come out at 38.41°S, 103.27°E — 838 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 51m of daylight. Shortest: 9h 29m.
  • 📏 At 97.0 square miles of land, 20659 is bigger than 77% of ZIP codes — room for about 74 Central Parks.
🌙 The sky over 20659 today
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🌋 Shake report
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Source: USGS.

People and housing

Population24,324This ZIP24,324
Households8,300This ZIP8,300
Housing units8,633This ZIP8,633
Median age37.5This ZIP37.5Maryland39.4US 38.9
Median household income$121,654This ZIP$121,654Maryland$103,678US $80,734
Median home value$416,900This ZIP$416,900Maryland$419,900US $332,700
Median gross rent$1,527This ZIP$1,527Maryland$1,705US $1,413
Bachelor's degree or higher27.5%This ZIP27.5%
Mean commute40.8 minThis ZIP40.8 min
Population density250.7 / sq miThis ZIP250.7 / sq mi

Business and tax activity

Business establishments328This ZIP328
Employees1,996This ZIP1,996
Annual payroll$99,819,000This ZIP$99,819,000
Tax returns filed11,710This ZIP11,710
Total adjusted gross income$1,051,272,000This ZIP$1,051,272,000

Land area

Land area97.01 sq miThis ZIP97.01 sq mi
Water area9.49 sq miThis ZIP9.49 sq mi

Counties 20659 spans

A ZIP code is a mail route and ignores county lines. Shares are by overlapping land area.

CountyShare of this ZIP
St. Mary's County 95.9%
Charles County 4.1%

Other place names in 20659

Census places whose land this ZIP code overlaps. The Postal Service may accept other city names in an address, too.

ZIP codes near 20659

ZIPCityDistance
20660 Morganza, MD 3.0 mi
20624 Clements, MD 4.8 mi
20656 Loveville, MD 5.5 mi
20621 Chaptico, MD 6.8 mi
20612 Benedict, MD 7.6 mi
20622 Charlotte Hall, MD 7.9 mi
20637 Hughesville, MD 8.2 mi
20609 Avenue, MD 8.8 mi
20627 Compton, MD 9.2 mi
20635 Helen, MD 9.4 mi

Find every ZIP code within 10 miles of 20659 →

Questions about this ZIP code

Where is ZIP code 20659?

20659 is in Mechanicsville, Maryland, in St. Mary's County, part of the Lexington Park, MD metropolitan area. Its published point location is 38.4079, -76.7320.

What county is 20659 in?

20659 spans 2 counties: St. Mary's County and Charles County. Most of it falls in St. Mary's County, measured by overlapping land area — the county holding the most land in a ZIP code is not always the one holding the most residents.

What area code is 20659?

Mechanicsville uses area codes 240, 301 and 227, from NANPA's telephone records.

What time zone is 20659 in?

20659 uses America/New_York.

How many people live in 20659?

About 24,324 people live in ZIP code 20659, in 8,300 households, at 250.7 people per square mile. These are American Community Survey 5-year estimates for the ZIP Code Tabulation Area, not a headcount.

What is the median household income in 20659?

$121,654 a year, against $103,678 across Maryland.

What ZIP codes are near 20659?

The closest are 20660 (3 mi), 20624 (4.8 mi), 20656 (5.5 mi), 20621 (6.8 mi) and 20612 (7.6 mi).

Is 20659 a PO Box ZIP code?

20659 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “20659 ZIP Code — Mechanicsville, Maryland (St. Mary's County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/20659

Machine-readable version of these facts:

curl https://zipcodes.pro/zip/20659.json

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