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zipcodes.pro — ZIP/20620

20620

ZIP 20620 is Callaway, Maryland, in St. Mary's County; Eastern time.

Type
Standard
Time zone
America/New_York
County
St. Mary's
Metro area
Lexington Park, MD
Population
1,115
Coordinates
38.2331, -76.5218
☼ Live from 20620 — Callaway, MD

Weather right now

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NEXRAD radar
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Local time: —

Where 20620 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 20620
  • 🔢 Type 20620 into a pocket calculator and turn it upside down: OZgOZ — not quite a word, sorry.
  • ➕ As a number, 20,620 = 2 × 2 × 5 × 1031. Its digits add up to 10, a total 513 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 101000010001100
  • 🏠 Its numerical neighbours: 20619 (California, MD, 4 mi away) and 20621 (Chaptico, MD, 16 mi away).
  • 🔄 Backwards, 20620 becomes 02602, which is not a ZIP code at all.
  • 👥 14 other ZIP codes are made of exactly the same digits (00622, 02026, 02062, 02206, 06022, 20026, …). The farthest-flung twin is 00622 in Boqueron, PR, 1,509 miles away.
  • 🧭 Farther south than 57% of all ZIP codes, and farther east than 83%.
  • 🎯1,186 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 20620 and you would come out at 38.23°S, 103.48°E — 823 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 50m of daylight. Shortest: 9h 30m.
  • 📏 At 4.3 square miles of land, 20620 is bigger than 17% of ZIP codes — room for about 3.3 Central Parks.
🌙 The sky over 20620 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population1,115This ZIP1,115
Households389This ZIP389
Housing units456This ZIP456
Median age41.6This ZIP41.6Maryland39.4US 38.9
Median household income$165,972This ZIP$165,972Maryland$103,678US $80,734
Median home value$391,300This ZIP$391,300Maryland$419,900US $332,700
Bachelor's degree or higher24.9%This ZIP24.9%
Mean commute21.1 minThis ZIP21.1 min
Population density260.1 / sq miThis ZIP260.1 / sq mi

Business and tax activity

Business establishments36This ZIP36
Employees452This ZIP452
Annual payroll$17,345,000This ZIP$17,345,000
Tax returns filed770This ZIP770
Total adjusted gross income$68,545,000This ZIP$68,545,000

Land area

Land area4.29 sq miThis ZIP4.29 sq mi
Water area0.02 sq miThis ZIP0.02 sq mi

Other place names in 20620

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

ZIP codes near 20620

ZIPCityDistance
20634 Great Mills, MD 1.4 mi
20692 Valley Lee, MD 3.8 mi
20619 California, MD 4.1 mi
20667 Park Hall, MD 4.2 mi
20653 Lexington Park, MD 5.1 mi
20690 Tall Timbers, MD 5.2 mi
20686 Saint Marys City, MD 5.8 mi
20630 Drayden, MD 6.0 mi
20674 Piney Point, MD 6.0 mi
20650 Leonardtown, MD 6.3 mi

Find every ZIP code within 10 miles of 20620 →

Questions about this ZIP code

Where is ZIP code 20620?

20620 is in Callaway, Maryland, in St. Mary's County, part of the Lexington Park, MD metropolitan area. Its published point location is 38.2331, -76.5218.

What county is 20620 in?

20620 lies in St. Mary's County.

What time zone is 20620 in?

20620 uses America/New_York.

How many people live in 20620?

About 1,115 people live in ZIP code 20620, in 389 households, at 260.1 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 20620?

$165,972 a year, against $103,678 across Maryland.

What ZIP codes are near 20620?

The closest are 20634 (1.4 mi), 20692 (3.8 mi), 20619 (4.1 mi), 20667 (4.2 mi) and 20653 (5.1 mi).

Is 20620 a PO Box ZIP code?

20620 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “20620 ZIP Code — Callaway, Maryland (St. Mary's County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/20620

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