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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/45231

45231

ZIP 45231 is in Cincinnati, Ohio, in Hamilton County; area codes 513 and 283; Eastern time. Cincinnati has 71 ZIP codes in all.

Type
Standard
Time zone
America/New_York
County
Hamilton
Population
40,463
Coordinates
39.2475, -84.5348
☼ Live from 45231 — Cincinnati, OH

Weather right now

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Local time: —

Where 45231 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 45231
  • 🔢 Type 45231 into a pocket calculator and turn it upside down: IEZSh — not quite a word, sorry.
  • ➕ As a number, 45,231 = 3 × 15077. Its digits add up to 15, a total 1,657 other ZIP codes share.
  • 💾In binary, the way a computer stores it: 1011000010101111
  • 🏠 Its numerical neighbours: 45230 (Cincinnati, OH, 14 mi away) and 45232 (Cincinnati, OH, 4 mi away).
  • 🔄 Backwards, 45231 becomes 13254, which is not a ZIP code at all.
  • 👥 66 other ZIP codes are made of exactly the same digits (12345, 12435, 12453, 12534, 12543, 13425, …). The farthest-flung twin is 34251 in Myakka City, FL, 831 miles away.
  • 🧭 Farther north than 51% of all ZIP codes, and farther east than 58%.
  • 🎯749 miles east of the geographic center of the Lower 48, near Lebanon, Kansas.
  • 🌏 Dig straight through the Earth from 45231 and you would come out at 39.25°S, 95.47°E — 1,248 miles from Perth, Australia, the nearest big city to that spot.
  • ☀Longest day of the year: 14h 56m of daylight. Shortest: 9h 24m.
  • 📏 At 14.8 square miles of land, 45231 is bigger than 32% of ZIP codes — room for about 11 Central Parks.
🌙 The sky over 45231 today
  • Working out the sun…
🌋 Shake report
  • Checking the USGS…

Source: USGS.

People and housing

Population40,463This ZIP40,463
Households16,911This ZIP16,911
Housing units17,505This ZIP17,505
Median age41.1This ZIP41.1Ohio39.7US 38.9
Median household income$71,353This ZIP$71,353Ohio$71,389US $80,734
Median home value$176,000This ZIP$176,000Ohio$214,800US $332,700
Median gross rent$1,232This ZIP$1,232Ohio$1,034US $1,413
Bachelor's degree or higher29.2%This ZIP29.2%
Mean commute24.6 minThis ZIP24.6 min
Population density2,737.5 / sq miThis ZIP2,737.5 / sq mi

Business and tax activity

Business establishments562This ZIP562
Employees7,532This ZIP7,532
Annual payroll$299,797,000This ZIP$299,797,000
Tax returns filed20,840This ZIP20,840
Total adjusted gross income$1,194,314,000This ZIP$1,194,314,000

Land area

Land area14.78 sq miThis ZIP14.78 sq mi
Water area0.21 sq miThis ZIP0.21 sq mi

Other place names in 45231

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

ZIP codes near 45231

ZIPCityDistance
45218 Cincinnati, OH 1.5 mi
45299 Cincinnati, OH 1.7 mi
45240 Cincinnati, OH 2.7 mi
45224 Cincinnati, OH 3.1 mi
45251 Cincinnati, OH 3.9 mi
45239 Cincinnati, OH 3.9 mi
45215 Cincinnati, OH 4.0 mi
45216 Cincinnati, OH 4.3 mi
45232 Cincinnati, OH 4.3 mi
45246 Cincinnati, OH 4.8 mi

Find every ZIP code within 10 miles of 45231 →

Questions about this ZIP code

Where is ZIP code 45231?

45231 is in Cincinnati, Ohio, in Hamilton County, part of the Cincinnati, OH-KY-IN metropolitan area. Its published point location is 39.2475, -84.5348.

What county is 45231 in?

45231 lies in Hamilton County.

What area code is 45231?

Cincinnati uses area codes 513 and 283, from NANPA's telephone records.

What time zone is 45231 in?

45231 uses America/New_York.

How many people live in 45231?

About 40,463 people live in ZIP code 45231, in 16,911 households, at 2,737.5 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 45231?

$71,353 a year, against $71,389 across Ohio.

What ZIP codes are near 45231?

The closest are 45218 (1.5 mi), 45299 (1.7 mi), 45240 (2.7 mi), 45224 (3.1 mi) and 45251 (3.9 mi).

Is 45231 a PO Box ZIP code?

45231 is a standard ZIP code. A normal ZIP code with street delivery.

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Cite this page

zipcodes.pro. “45231 ZIP Code — Cincinnati, Ohio (Hamilton County).” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/zip/45231

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