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 — CITY/CT/GUILFORD

Guilford ZIP code, Connecticut

The ZIP code for Guilford, CT is 06437, and its area codes are 203 and 475.

USPS city name
1 ZIP code
Population
22,067
Area codes
203, 475

Guilford in numbers

About 22,067 people live in Guilford, in 8,856 households. The median household income is $137,615 a year, 44% above the Connecticut median of $95,781 (US: $80,734). The median owner-occupied home is valued at $515,000 (40% above the Connecticut median).

Population22,067Guilford22,067
Households8,856Guilford8,856
Median household income$137,615Guilford$137,615Connecticut$95,781US $80,734
Median home value$515,000Guilford$515,000Connecticut$366,900US $332,700

U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates, for the ZIP code addressed as Guilford. Survey estimates carry margins of error, wider for small places. Sources and methods.

ZIP codes addressed as Guilford

ZIP codes with the USPS city name Guilford
ZIP City Type Population Median income Median home
06437 Guilford , CT Standard 22,067 $137,615 $515,000

Map of Guilford ZIP codes

06437

The ZIP codes of Guilford, CT, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.

Towns near Guilford

The nearest larger towns are East Haven (27,806 people, 8.8 mi), North Haven (24,336 people, 9.0 mi) and New Haven (134,349 people, 12 mi).

Towns near Guilford
TownPopulationDistance
Northford 6,186 6.3 mi
Branford Center 6,305 7.2 mi
East Haven 27,806 8.8 mi
North Haven 24,336 9.0 mi
Durham 3,347 9.5 mi
Clinton 3,465 9.5 mi
Wallingford Center 18,208 10.3 mi
Quinnipiac University 4,311 11.9 mi
New Haven 134,349 11.9 mi
Westbrook Center 2,501 13.7 mi
West Haven 55,351 14.6 mi
Meriden 60,545 15.0 mi
Middletown 47,958 15.1 mi
Cheshire Village 6,172 15.8 mi

More nearby: every ZIP code in New Haven County · Connecticut ZIP codes

Cite this page

zipcodes.pro. “Guilford, CT ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/city/ct/guilford

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