--- title: "Area code 475: Connecticut, United States" url: "https://lookvalid.com/area-code/475.md" canonical_url: "https://lookvalid.com/area-code/475" last_updated: "2026-10-23" type: "reference" summary: "Area code 475 serves Connecticut, United States. Number formats, numbering rules, a live phone validator and the other codes in Connecticut." --- # Area code 475: Connecticut, United States Area code 475 serves Connecticut, United States. Number formats, numbering rules, a live phone validator and the other codes in Connecticut. NANPA lists 284 central office codes (prefixes) in use in area code 475, held by 31 holders across 32 rate centers. Onvoy holds the most prefixes, 59 (21%). 100% of the prefixes are pooled, which means their thousands-blocks can belong to different companies. The FCC unwanted-call data has 1,208 complaints on file for 1,022 numbers in 475, most often filed as "Unwanted Calls". These are consumer reports, not findings. ## Facts - In service since: 2009-12-12 - Time zone: Eastern (E) - Assigned overlays: 203 (1947-01-01) - Prefixes in use: 284 - Pooled prefixes: 284 (100%) - Rate centers: 32 - Companies holding prefixes: 31 - Assignment dates on file: 2009-08-07 to 2026-08-06 (281 prefixes) - ZIP codes in its places: 120 ## Rate centers | Rate center | Prefixes | Share | | --- | --- | --- | | NEW HAVEN | 42 | 15% | | STAMFORD | 27 | 10% | | BRIDGEPORT | 25 | 9% | | NORWALK | 22 | 8% | | ANSONIDRBY | 18 | 6% | | DANBURY | 18 | 6% | | WATERBURY | 18 | 6% | | HUNTINGTON | 9 | 3% | | 24 other rate centers | 105 | 37% | ## Carriers | Holder | Prefixes | Share | | --- | --- | --- | | Onvoy | 59 | 21% | | Verizon Wireless | 47 | 17% | | Omnipoint Communications | 39 | 14% | | Bandwidth.com CLEC | 18 | 6% | | New Cingular Wireless PCS | 18 | 6% | | Ton80 Communications | 17 | 6% | | 25 other carriers | 86 | 30% | A prefix holder is the company a code was assigned to, not necessarily a number's current carrier, because numbers can be ported to another company. ## History - 1947-01-01: Area code 203, named as the parent of 475 in the NANPA report, was in service. - 2009-12-12: Area code 475 went into service. ## Nearest area codes The area codes closest to 475, measured between the centers of the ZIP code places they serve, are 934 (about 31 miles), 631 (about 32 miles), 516 (about 35 miles), 914 (about 38 miles) and 860 (about 41 miles). ## ZIP codes 120 ZIP codes fall in places that have a rate center in this area code. The places with the most are New Haven, CT (28 ZIP codes), Stamford, CT (17 ZIP codes) and Waterbury, CT (16 ZIP codes). A ZIP code and an area code are unrelated systems, so a ZIP code can sit in more than one area code and an area code spans many ZIP codes. ## Complaints on file 1,208 complaints for 1,022 numbers. Numbers whose latest complaint falls in each year: - 2023: 101 - 2024: 166 - 2025: 134 ## Questions ### Where is area code 475? NANPA assigns area code 475 to Connecticut, United States. ### In which state does area code 475 sit? Connecticut. 475 is one of 4 area codes the NANPA table assigns to the state. ### Which places does area code 475 cover? The places with the most ZIP codes among the rate centers in 475 are New Haven, CT, Stamford, CT and Waterbury, CT. The rate center list on this page shows all of them. ### Who owns area code 475? NANPA assigns area codes. Within 475, Onvoy holds the most prefixes, 59 prefixes or 21%. ### Which time zone does 475 use? The NANPA NPA report lists the time zone for 475 as Eastern (E). ### What year did 475 enter service? The NANPA NPA report gives an in-service date of 2009-12-12, so 475 has been in use since 2009. ### Does area code 475 have an overlay? Yes. 203 (in service 1947-01-01) shares the same area with 475, so numbers from all of them are local to each other. ### Which area codes are nearest to 475? The area codes closest to 475, measured between the centers of the ZIP code places they serve, are 934 (about 31 miles), 631 (about 32 miles), 516 (about 35 miles), 914 (about 38 miles) and 860 (about 41 miles). ### How many prefixes does area code 475 have? NANPA's report dated 2026-10-17 lists 284 prefixes in service in 475, spread over 32 rate centers and 31 holders. ### Are there complaints about 475 numbers? The FCC data on file has 1,208 complaints for 1,022 numbers in 475. They are unverified consumer reports. A number with no complaints on file is not proven safe. Sources: NANPA central office code report dated 2026-10-17; NANPA NPA report dated 2026-10-18; FCC unwanted-call complaints, data fetched 2026-10-17; ZIP code places from GeoNames (CC BY 4.0).