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 — PREFIX/423

ZIP codes starting with 423

ZIP codes
45
States
KY
Largest city
Owensboro, KY
Population
176,211

The first three digits of a ZIP code identify a sectional center facility — the postal processing plant that sorts mail for the area. It is a mail-routing grouping, not an administrative boundary.

Every ZIP code in 423xx

ZIP codes starting with 423
ZIP City Type Population Median income Median home
42301 Owensboro , KY Standard 45,445 $66,885 $198,200
42302 Owensboro , KY No street area — — —
42303 Owensboro , KY Standard 42,119 $64,773 $198,200
42304 Owensboro , KY No street area — — —
42320 Beaver Dam , KY Standard 9,128 $54,730 $150,200
42321 Beech Creek , KY Standard 553 $53,750 $79,800
42322 Beech Grove , KY Standard 53 — —
42323 Beechmont , KY Standard 852 $53,438 $161,900
42324 Belton , KY Standard 1,228 $77,898 $157,900
42325 Bremen , KY Standard 2,045 $78,750 $133,600
42326 Browder , KY Standard 283 $42,167 $162,500
42327 Calhoun , KY Standard 4,206 $66,836 $167,500
42328 Centertown , KY Standard 1,158 $57,679 $97,200
42330 Central City , KY Standard 9,367 $50,226 $151,200
42332 Cleaton , KY Standard 20 — —
42333 Cromwell , KY Standard 644 $33,969 $85,000
42334 Curdsville , KY No street area — — —
42337 Drakesboro , KY Standard 1,683 $36,875 $75,500
42338 Dundee , KY Standard 12 — —
42339 Dunmor , KY Standard 840 $46,667 $110,700
42343 Fordsville , KY Standard 1,267 $52,679 $86,700
42344 Graham , KY Standard 763 $40,972 $83,900
42345 Greenville , KY Standard 11,440 $62,222 $138,500
42347 Hartford , KY Standard 5,829 $60,900 $134,500
42348 Hawesville , KY Standard 4,713 $56,500 $120,900
42349 Horse Branch , KY Standard 1,962 $58,601 $88,900
42350 Island , KY Standard 1,342 $103,875 $168,000
42351 Lewisport , KY Standard 4,587 $76,213 $169,200
42352 Livermore , KY Standard 1,955 $53,750 $143,000
42354 Mc Henry , KY Standard 283 $65,625 $102,100
42355 Maceo , KY Standard 1,465 $60,125 $144,900
42356 Maple Mount , KY Standard 132 — —
42361 Olaton , KY Standard 425 $43,750 $89,100
42364 Pellville , KY No street area — — —
42366 Philpot , KY Standard 5,851 $87,672 $229,700
42367 Powderly , KY Standard 949 $51,397 $100,400
42368 Reynolds Station , KY Standard 989 $76,208 $158,000
42369 Rockport , KY Standard 223 $62,750 $77,300
42370 Rosine , KY Standard 16 — —
42371 Rumsey , KY Standard 472 $130,250 $163,900
42372 Sacramento , KY Standard 1,389 $48,090 $102,900
42374 South Carrollton , KY Standard 124 $41,534 $123,100
42376 Utica , KY Standard 6,886 $76,098 $207,900
42377 West Louisville , KY No street area — — —
42378 Whitesville , KY Standard 3,513 $73,419 $181,400

Cite this page

zipcodes.pro. “ZIP codes starting with 423.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/prefix/423

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