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/CT/MOST-TAX-RETURNS

ZIP Codes With the Most Tax Returns Filed in Connecticut

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 06902 Stamford Fairfield 36,200
2 06010 Bristol Hartford 31,470
3 06810 Danbury Fairfield 27,270
4 06516 West Haven New Haven 26,690
5 06492 Wallingford New Haven 23,400
6 06457 Middletown Middlesex 23,190
7 06606 Bridgeport Fairfield 23,040
8 06484 Shelton Fairfield 22,390
9 06511 New Haven New Haven 21,900
10 06082 Enfield Hartford 21,090
11 06460 Milford New Haven 20,530
12 06614 Stratford Fairfield 18,390
13 06611 Trumbull Fairfield 18,360
14 06450 Meriden New Haven 18,350
15 06360 Norwich New London 18,340
16 06040 Manchester Hartford 18,190
17 06790 Torrington Litchfield 18,140
18 06489 Southington Hartford 17,300
19 06513 New Haven New Haven 16,690
20 06053 New Britain Hartford 16,560
21 06111 Newington Hartford 16,460
22 06095 Windsor Hartford 16,400
23 06066 Vernon Rockville Tolland 16,020
24 06770 Naugatuck New Haven 15,950
25 06405 Branford New Haven 15,720
26 06512 New Haven New Haven 15,700
27 06811 Danbury Fairfield 15,540
28 06106 Hartford Hartford 15,400
29 06824 Fairfield Fairfield 15,260
30 06854 Norwalk Fairfield 15,110
31 06851 Norwalk Fairfield 15,070
32 06033 Glastonbury Hartford 14,970
33 06708 Waterbury New Haven 14,790
34 06118 East Hartford Hartford 14,630
35 06109 Wethersfield Hartford 14,620
36 06340 Groton New London 14,120
37 06051 New Britain Hartford 14,100
38 06776 New Milford Litchfield 13,850
39 06410 Cheshire New Haven 13,800
40 06514 Hamden New Haven 13,590
41 06074 South Windsor Hartford 13,490
42 06473 North Haven New Haven 13,200
43 06705 Waterbury New Haven 12,970
44 06880 Westport Fairfield 12,920
45 06320 New London New London 12,780
46 06042 Manchester Hartford 12,660
47 06451 Meriden New Haven 12,530
48 06002 Bloomfield Hartford 12,510
49 06108 East Hartford Hartford 12,230
50 06830 Greenwich Fairfield 12,170

Showing the top 50 of 262 ZIP codes in Connecticut that have this figure . 06902 ranks 1st at 36,200, against 12,170 in 50th place.

Other rankings for Connecticut

Cite this page

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

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