--- title: "Area code 641: Iowa, United States" url: "https://lookvalid.com/area-code/641.md" canonical_url: "https://lookvalid.com/area-code/641" last_updated: "2026-10-23" type: "reference" summary: "Area code 641 serves Iowa, United States. Number formats, numbering rules, a live phone validator and the other codes in Iowa." --- # Area code 641: Iowa, United States Area code 641 serves Iowa, United States. Number formats, numbering rules, a live phone validator and the other codes in Iowa. NANPA lists 584 central office codes (prefixes) in use in area code 641, held by 72 holders across 223 rate centers. Windstream Iowa Communications holds the most prefixes, 60 (10%). 72% of the prefixes are pooled, which means their thousands-blocks can belong to different companies. The FCC unwanted-call data has 724 complaints on file for 634 numbers in 641, most often filed as "Unwanted Calls". These are consumer reports, not findings. ## Facts - In service since: 2000-07-09 - Time zone: Central (C) - Prefixes in use: 584 - Pooled prefixes: 418 (72%) - Rate centers: 223 - Companies holding prefixes: 72 - Assignment dates on file: 2001-02-09 to 2026-06-11 (250 prefixes) - ZIP codes in its places: 187 ## Rate centers | Rate center | Prefixes | Share | | --- | --- | --- | | MASON CITY | 20 | 3% | | NEW HAVEN | 17 | 3% | | MARSHALLTN | 16 | 3% | | OTTUMWA | 15 | 3% | | NEWHAMPTON | 12 | 2% | | OSKALOOSA | 12 | 2% | | PELLA | 12 | 2% | | CHARLES CY | 11 | 2% | | 215 other rate centers | 469 | 80% | ## Carriers | Holder | Prefixes | Share | | --- | --- | --- | | Windstream Iowa Communications | 60 | 10% | | Verizon Wireless | 46 | 8% | | United States Cellular | 39 | 7% | | Windstream Iowa Communications, INC. - North | 32 | 5% | | Qwest | 30 | 5% | | Onvoy Spectrum | 29 | 5% | | 66 other carriers | 348 | 60% | 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 515, named as the parent of 641 in the NANPA report, was in service. - 2000-07-09: Area code 641 went into service. ## Nearest area codes The area codes closest to 641, measured between the centers of the ZIP code places they serve, are 515 (about 33 miles), 319 (about 73 miles), 563 (about 116 miles), 712 (about 116 miles) and 660 (about 153 miles). ## ZIP codes 187 ZIP codes fall in places that have a rate center in this area code. The places with the most are Fairfield, IA (2 ZIP codes), Mason City, IA (2 ZIP codes) and Ackley, IA (1 ZIP code). 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 724 complaints for 634 numbers. Numbers whose latest complaint falls in each year: - 2023: 34 - 2024: 28 - 2025: 47 ## Questions ### Where is area code 641? NANPA assigns area code 641 to Iowa, United States. ### In which state does area code 641 sit? Iowa. 641 is one of 5 area codes the NANPA table assigns to the state. ### Which places does area code 641 cover? The places with the most ZIP codes among the rate centers in 641 are Fairfield, IA, Mason City, IA and Ackley, IA. The rate center list on this page shows all of them. ### Who owns area code 641? NANPA assigns area codes. Within 641, Windstream Iowa Communications holds the most prefixes, 60 prefixes or 10%. ### Which time zone does 641 use? The NANPA NPA report lists the time zone for 641 as Central (C). ### What year did 641 enter service? The NANPA NPA report gives an in-service date of 2000-07-09, so 641 has been in use since 2000. ### Does area code 641 have an overlay? The NANPA NPA report lists no other area code in an overlay with 641. ### Which area codes are nearest to 641? The area codes closest to 641, measured between the centers of the ZIP code places they serve, are 515 (about 33 miles), 319 (about 73 miles), 563 (about 116 miles), 712 (about 116 miles) and 660 (about 153 miles). ### How many prefixes does area code 641 have? NANPA's report dated 2026-10-17 lists 584 prefixes in service in 641, spread over 223 rate centers and 72 holders. ### Are there complaints about 641 numbers? The FCC data on file has 724 complaints for 634 numbers in 641. 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).