Middlesex

Source:

Connecticut

Middlesex is a county in Connecticut with 22 ZIP codes and a total population of 164,856. All data is sourced from the U.S. Census Bureau American Community Survey (ACS) 2023 5-Year Estimates.

Middlesex is a county inside Connecticut (FIPS code 09007) that contains 22 USPS ZIP codes covering a combined population of 164,856 according to Census ACS 5-Year Estimates. Counties are the natural bridge between state-level summaries and ZIP-level detail — crime statistics, HUD Fair Market Rents, and childcare pricing are all published at the county level, while household income and housing values are published at the ZIP level. This page reconciles the two views so you can see which ZIPs drive the county totals.

The 22 ZIPs listed below are ordered by population and each links to the full ZIP detail page with Census demographics, housing, income, home-price history, and cross-agency inputs. The most populated ZIP in Middlesex is 06457 covering Middletown with 47,648 residents at 449 people per square mile. Population density across ZIPs in this county varies — use the density column to spot urban cores versus rural delivery areas. A single county can contain both a dense downtown ZIP and a large rural ZIP covering several hundred square miles.

Because Middlesex uses FIPS code 09007, it joins cleanly to county-level federal datasets: HUD Fair Market Rent tables, FBI Uniform Crime Report data, and the Department of Labor National Database of Childcare Prices all key off the same code. That is how neighborhood scorecards combine ZIP-level Census demographics with county-level safety and affordability metrics. All data on this page comes from U.S. Census Bureau ACS 2023 5-Year Estimates and USPS ZIP Code Tabulation Area files — no estimates, no proprietary sources, no editorial scoring.

22

Total ZIPs

164,856

Total Population

ZIP Codes in Middlesex

Side-by-side: Compare 06457 vs 06416 →

ZIP Code City Population Density
06457 Middletown 47,648 449
06416 Cromwell 14,005 466
06413 Clinton 13,235 316
06424 East Hampton 12,808 123
06475 Old Saybrook 10,242 263
06480 Portland 9,508 157
06422 Durham 7,388 121
06498 Westbrook 6,963 170
06419 Killingworth 6,525 71
06441 Higganum 5,438 81
06423 East Haddam 5,097 51
06417 Deep River 4,629 132
06412 Chester 3,994 96
06426 Essex 3,245 219
06469 Moodus 3,209 123
06455 Middlefield 3,148 112
06442 Ivoryton 2,745 318
06438 Haddam 2,550 80
06481 Rockfall 1,277 274
06409 Centerbrook 693 198
06456 Middle Haddam 295 131
06414 Cobalt 214 285

What are common questions about ZIP codes in this county?

What is the population of Middlesex?
Middlesex has a total population of 164,856 across 22 ZIP codes, based on U.S. Census Bureau ACS 2023 data.
What ZIP codes are in Middlesex?
Middlesex includes 22 ZIP codes: 06457, 06416, 06413, 06424, 06475, 06480, 06422, 06498, 06419, 06441, and more.
What is the median household income in Middlesex?
Median household income data for individual ZIP codes in Middlesex is available on each ZIP code's detail page. Visit any ZIP code link below to see income, housing, and demographic data.

Source: U.S. Census Bureau, American Community Survey (ACS) 5-Year Estimates (2023). Verify with Census Bureau →

Source: HUD USPS Crosswalk (ZIP-to-county mapping). Verify with HUD →

PlainZIP is not affiliated with the U.S. Census Bureau or any government agency.