Every ZIP code in the United States, with weather, radar, trivia and the numbers behind it. Five digits since 1963!

ZIP stands for Zone Improvement Plan. The codes went live on July 1, 1963.The lowest ZIP code is 00501 — the IRS in Holtsville, New York.The highest ZIP code is 99950, in Ketchikan, Alaska.Type 07734 into a calculator and turn it upside down: hELLO. It is Keansburg, New Jersey.12345 belongs to one company: General Electric in Schenectady, New York.The first digit is a region: 0 is New England and New Jersey, 9 is the West Coast, Alaska and Hawaii.Mr. ZIP, the cartoon mailman, was the mascot that sold the idea to America.ZIP+4 arrived in 1983 and can narrow a ZIP down to one side of one block.A ZIP code is a mail route, not a place: plenty of them cross county and even state lines.Play ZIP Hunt: guess the secret ZIP code of the day in six tries.
zipcodes.pro — ZIP/17821

17821

ZIP 17821 is in Danville, Pennsylvania, mostly in Montour County; area codes 570 and 272; Eastern time. Danville has 2 ZIP codes; the other is 17822.

Type
Standard
Time zone
America/New_York
County
Montour +2 more
Metro area
Sunbury, PA
Population
18,613
Coordinates
40.9901, -76.6442
☼ Live from 17821 — Danville, PA

Weather right now

Asking the National Weather Service…

NEXRAD radar
Finding the nearest radar…
Local time: —

Where 17821 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 17821
  • 🔢 Type 17821 into a pocket calculator and turn it upside down: IZBLI — not quite a word, sorry.
  • ➕ As a number, 17,821 = 71 × 251. Its digits add up to 19, a total 2,454 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 100010110011101
  • 🏠 Its numerical neighbours: 17820 (Catawissa, PA, 14 mi away) and 17822 (Danville, PA, 3 mi away).
  • 🔄 Backwards, 17821 becomes 12871 — and that is a real ZIP code: Schuylerville, NY, 213 miles away.
  • 👥 25 other ZIP codes are made of exactly the same digits (11782, 12187, 12781, 12817, 12871, 17128, …). The farthest-flung twin is 87121 in Albuquerque, NM, 1,688 miles away.
  • 🧭 Farther north than 67% of all ZIP codes, and farther east than 83%.
  • 🎯1,154 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 17821 and you would come out at 40.99°S, 103.36°E — 932 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 15h 08m of daylight. Shortest: 9h 13m.
  • 📏 At 134.5 square miles of land, 17821 is bigger than 84% of ZIP codes — room for about 102 Central Parks.
🌙 The sky over 17821 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population18,613This ZIP18,613
Households8,017This ZIP8,017
Housing units8,288This ZIP8,288
Median age42.9This ZIP42.9Pennsylvania40.9US 38.9
Median household income$76,971This ZIP$76,971Pennsylvania$77,971US $80,734
Median home value$249,500This ZIP$249,500Pennsylvania$254,500US $332,700
Median gross rent$1,163This ZIP$1,163Pennsylvania$1,209US $1,413
Bachelor's degree or higher39.1%This ZIP39.1%
Mean commute19.5 minThis ZIP19.5 min
Population density138.4 / sq miThis ZIP138.4 / sq mi

Business and tax activity

Business establishments434This ZIP434
Employees7,024This ZIP7,024
Annual payroll$434,287,000This ZIP$434,287,000
Tax returns filed9,520This ZIP9,520
Total adjusted gross income$852,264,000This ZIP$852,264,000

Land area

Land area134.50 sq miThis ZIP134.50 sq mi
Water area2.66 sq miThis ZIP2.66 sq mi

Counties 17821 spans

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

CountyShare of this ZIP
Montour County 70.5%
Northumberland County 23.5%
Columbia County 6.0%

Other place names in 17821

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

ZIP codes near 17821

ZIPCityDistance
17868 Riverside, PA 2.5 mi
17822 Danville, PA 2.6 mi
17884 Washingtonville, PA 4.6 mi
17865 Potts Grove, PA 7.6 mi
17877 Snydertown, PA 7.8 mi
17857 Northumberland, PA 7.8 mi
17847 Milton, PA 8.8 mi
17772 Turbotville, PA 10.0 mi
17749 Mc Ewensville, PA 10.5 mi
17860 Paxinos, PA 10.6 mi

Find every ZIP code within 10 miles of 17821 →

Questions about this ZIP code

Where is ZIP code 17821?

17821 is in Danville, Pennsylvania, in Montour County, part of the Sunbury, PA micropolitan area. Its published point location is 40.9901, -76.6442.

What county is 17821 in?

17821 spans 3 counties: Montour County, Northumberland County and Columbia County. Most of it falls in Montour 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 17821?

Danville uses area codes 570 and 272, from NANPA's telephone records.

What time zone is 17821 in?

17821 uses America/New_York.

How many people live in 17821?

About 18,613 people live in ZIP code 17821, in 8,017 households, at 138.4 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 17821?

$76,971 a year, against $77,971 across Pennsylvania.

What ZIP codes are near 17821?

The closest are 17868 (2.5 mi), 17822 (2.6 mi), 17884 (4.6 mi), 17865 (7.6 mi) and 17877 (7.8 mi).

Is 17821 a PO Box ZIP code?

17821 is a standard ZIP code. A normal ZIP code with street delivery.

Download or cite

Cite this page

zipcodes.pro. “17821 ZIP Code — Danville, Pennsylvania (Montour County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/17821

Machine-readable version of these facts:

curl https://zipcodes.pro/zip/17821.json

Underlying data is public domain or openly licensed — sources, vintages and licences.