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 — RANKINGS/PA/MOST-TAX-RETURNS

ZIP Codes With the Most Tax Returns Filed in Pennsylvania

What this measures. Number of individual income tax returns filed. A rough proxy for how many households a ZIP code contains, available where census figures are not. Source: IRS Statistics of Income, ZIP code data, data release 2026-10-12.

# ZIP City County Returns filed
1 17603 Lancaster Lancaster 33,280
2 19446 Lansdale Montgomery 29,600
3 17331 Hanover York 29,210
4 19111 Philadelphia Philadelphia 28,710
5 15601 Greensburg Westmoreland 28,680
6 17601 Lancaster Lancaster 28,650
7 19020 Bensalem Bucks 28,240
8 19143 Philadelphia Philadelphia 28,190
9 19120 Philadelphia Philadelphia 27,580
10 19124 Philadelphia Philadelphia 27,250
11 19067 Morrisville Bucks 27,170
12 19335 Downingtown Chester 26,760
13 19380 West Chester Chester 26,460
14 19320 Coatesville Chester 26,180
15 17602 Lancaster Lancaster 25,390
16 19382 West Chester Chester 25,060
17 18103 Allentown Lehigh 24,830
18 19464 Pottstown Montgomery 24,770
19 18104 Allentown Lehigh 24,340
20 15642 Irwin Westmoreland 24,080
21 17543 Lititz Lancaster 23,990
22 19403 Norristown Montgomery 23,920
23 19148 Philadelphia Philadelphia 23,820
24 15301 Washington Washington 23,510
25 18102 Allentown Lehigh 23,410
26 18974 Warminster Bucks 23,100
27 17055 Mechanicsburg Cumberland 22,790
28 15237 Pittsburgh Allegheny 22,740
29 19149 Philadelphia Philadelphia 22,310
30 17050 Mechanicsburg Cumberland 22,210
31 15317 Canonsburg Washington 22,150
32 19460 Phoenixville Chester 22,150
33 19145 Philadelphia Philadelphia 22,100
34 19134 Philadelphia Philadelphia 21,620
35 19146 Philadelphia Philadelphia 21,340
36 15108 Coraopolis Allegheny 21,040
37 17042 Lebanon Lebanon 20,550
38 18017 Bethlehem Northampton 20,310
39 17112 Harrisburg Dauphin 20,180
40 18966 Southampton Bucks 20,170
41 19426 Collegeville Montgomery 20,130
42 19147 Philadelphia Philadelphia 20,000
43 17404 York York 19,710
44 16001 Butler Butler 19,670
45 18042 Easton Northampton 19,540
46 19063 Media Delaware 19,480
47 19140 Philadelphia Philadelphia 19,210
48 19128 Philadelphia Philadelphia 19,160
49 17403 York York 19,150
50 17701 Williamsport Lycoming 18,950

Showing the top 50 of 1,362 ZIP codes in Pennsylvania that have this figure . 17603 ranks 1st at 33,280, against 18,950 in 50th place.

Other rankings for Pennsylvania

Cite this page

zipcodes.pro. “ZIP Codes With the Most Tax Returns Filed in Pennsylvania.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/rankings/pa/most-tax-returns

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