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zipcodes.pro — ZIP/57720

57720

ZIP 57720 is Buffalo, South Dakota, in Harding County; area code 605; Mountain time.

Type
Standard
Time zone
America/Denver
County
Harding
Metro area
none
Population
518
Coordinates
45.5372, -103.5861
☼ Live from 57720 — Buffalo, SD

Weather right now

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NEXRAD radar
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Local time: —

Where 57720 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 57720
  • 🔢 Type 57720 into a pocket calculator and turn it upside down: OZLLS — not quite a word, sorry.
  • ➕ As a number, 57,720 = 2 × 2 × 2 × 3 × 5 × 13 × 37. Its digits add up to 21, a total 2,594 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 1110000101111000
  • 🏠 Its numerical neighbours: 57719 (Box Elder, SD, 95 mi away) and 57722 (Buffalo Gap, SD, 148 mi away).
  • 🔄 Backwards, 57720 becomes 02775, which is not a ZIP code at all.
  • 👥 31 other ZIP codes are made of exactly the same digits (05772, 07752, 20577, 20757, 20775, 25707, …). The farthest-flung twin is 07752 in Navesink, NJ, 1,527 miles away.
  • 🧭 Farther north than 93% of all ZIP codes, and farther west than 82%.
  • 🎯469 miles northwest of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 57720 and you would come out at 45.54°S, 76.41°E — 391 miles from Port-aux-Français, French Southern Territories, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 41m of daylight. Shortest: 8h 42m.
  • 📏 At 1,296.2 square miles of land, 57720 is bigger than 99% of ZIP codes — room for about 984 Central Parks.
🌙 The sky over 57720 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population518This ZIP518
Households264This ZIP264
Housing units378This ZIP378
Median age52.3This ZIP52.3South Dakota38.0US 38.9
Median household income$79,091This ZIP$79,091South Dakota$75,081US $80,734
Median home value$157,000This ZIP$157,000South Dakota$257,400US $332,700
Median gross rent$586This ZIP$586South Dakota$946US $1,413
Bachelor's degree or higher25.0%This ZIP25.0%
Mean commute14.0 minThis ZIP14.0 min
Population density0.4 / sq miThis ZIP0.4 / sq mi

Business and tax activity

Business establishments35This ZIP35
Employees318This ZIP318
Annual payroll$21,715,000This ZIP$21,715,000
Tax returns filed310This ZIP310
Total adjusted gross income$24,949,000This ZIP$24,949,000

Land area

Land area1,296.16 sq miThis ZIP1,296.16 sq mi
Water area4.19 sq miThis ZIP4.19 sq mi

Other place names in 57720

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

ZIP codes near 57720

ZIPCityDistance
57724 Camp Crook, SD 20.2 mi
57776 Redig, SD 21.1 mi
57755 Ludlow, SD 25.6 mi
57651 Reva, SD 27.0 mi
59319 Capitol, MT 29.4 mi
57650 Ralph, SD 33.5 mi
57649 Prairie City, SD 35.8 mi
58623 Bowman, ND 43.8 mi
58653 Scranton, ND 44.1 mi
57717 Belle Fourche, SD 44.3 mi

Find every ZIP code within 10 miles of 57720 →

Questions about this ZIP code

Where is ZIP code 57720?

57720 is in Buffalo, South Dakota, in Harding County. Its published point location is 45.5372, -103.5861.

What county is 57720 in?

57720 lies in Harding County.

What area code is 57720?

Buffalo uses area code 605, from NANPA's telephone records.

What time zone is 57720 in?

57720 uses America/Denver.

How many people live in 57720?

About 518 people live in ZIP code 57720, in 264 households, at 0.4 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 57720?

$79,091 a year, against $75,081 across South Dakota.

What ZIP codes are near 57720?

The closest are 57724 (20.2 mi), 57776 (21.1 mi), 57755 (25.6 mi), 57651 (27 mi) and 59319 (29.4 mi).

Is 57720 a PO Box ZIP code?

57720 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “57720 ZIP Code — Buffalo, South Dakota (Harding County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/57720

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