641 Area Code: Mason City, Iowa
Area code 641 serves Mason City, New Haven and Marshalltown, Iowa in the Central time zone, in service since 2000. Consumers have filed 1,635 unwanted-call complaints against 1,506 different 641 numbers, 296 of them with the FTC in the last 30 days. Look up the exact number that called you below.
Area code 641 at a glance
- State
- Iowa
- Main cities
- Mason City, New Haven, Marshalltown, Ottumwa, Oskaloosa, Pella + 216 more
- Counties
- Mitchell County, Marshall County, Cerro Gordo County, Wapello County + 42 more
- Local time
- —Central
- In service since
- July 9, 2000
- Split from
- 515
- Local dialing
- 7 digits allowed
- Exchanges
- 223 rate centers, 584 prefixes
Sources: NANPA area code and central office code records (refreshed weekly); cities and counties matched from US Census Bureau and USGS place names.
Reported 641 numbers
No single 641 number has enough complaints yet for a full report page, so none are listed. Look up the exact number that called you: the lookup works on every US number, whether or not it has complaint history.
What calls from 641 numbers are about
914 FTC Do Not Call complaints about 641 numbers since Jul 24. The most common named subject is debt-relief pitches, at 27% of complaints (90% of those were recorded messages). Overall, 80% of callers who answered said the call was a robocall.
FTC complaint subjects
- Other / unspecified40244%
- Debt reduction25127%
- Medical & prescriptions809%
- Impostor (government, business, family)617%
- Dropped call / no message576%
- No subject given404%
- Warranties & protection plans91%
FCC complaints by call type, last 2 years
- Prerecorded Voice6667%
- Live Voice2525%
- Text Message88%
Live-voice calls are from a person; prerecorded calls are robocalls.
When 641 spam calls come in
31% of complaints that give a call time describe calls between 1pm and 4pm. 90% came Monday to Friday, most on Tuesdays, the pattern of call-center robocall campaigns that run on business hours. Times are as consumers reported them to the FTC.
By hour of the day
By day of the week
Is it getting worse?
283 FTC complaints about 641 numbers in the last four weeks, down 4% on the four weeks before. FCC complaints about 641 numbers peaked in 2017 (101); the FTC's daily Do Not Call data has carried most of the volume since mid-2026.
FTC complaints per week
FCC complaints per year
Years shown as '15 to '26; the current year is partial.
Who gets these calls
Only 36% of the FTC complaints about 641 numbers came from Iowa residents; the most came from California, Florida and Texas. 641 numbers are being used for nationwide campaigns, so the area code says little about where the caller is.
Where complainants live
- Iowa33236%
- California728%
- Florida455%
- Texas394%
- New York364%
What people with 641 numbers report
People whose own number starts with 641 filed 597 FTC complaints since Jul 24. 52% were about calls showing another 641 number. The most common named subject was debt-relief pitches.
Area codes on the calls they reported
- 641 (same code)31352%
- 833 (toll-free)275%
- 515183%
- 877 (toll-free)183%
- 866 (toll-free)163%
Likely campaigns using 641 numbers
Groups of numbers that drew the same FTC complaint in the same pattern over the last 60 days. The grouping is statistical and doesn't identify who is calling.
Busiest 641 prefixes this month
FTC complaints in the last 30 days, grouped by the first six digits. When one prefix collects complaints about many different numbers, a campaign is usually cycling through that block. The carrier is who NANPA assigned the prefix to, not who made the calls.
| Prefix | Complaints | Numbers | Carrier | Exchange |
|---|---|---|---|---|
| (641) 247-xxxx | 21 | 21 | UScellular | Fontanelle |
| (641) 888-xxxxcampaign | 19 | 19 | Verizon Wireless (Cellco Partnership) | Grinnell |
| (641) 923-xxxx | 17 | 17 | Qwest (CenturyLink / Lumen) | Garner |
| (641) 300-xxxx | 12 | 11 | Fractel, LLC | Osage |
| (641) 400-xxxx | 10 | 10 | Onvoy (Sinch) | Humeston |
Carriers operating in 641
NANPA has assigned 584 641 prefixes (NPA-NXX central-office codes) across 223 rate centers: 26% to wireless carriers, 73% to landline and VoIP operators; 72% are pooled blocks shared by several carriers. 2 prefixes were assigned in the last 12 months (newest 2026-06-11). The carrier holding a prefix is who the number was issued through. It says nothing about who is calling, since caller ID is routinely spoofed.
| Carrier | Type | Prefixes | Rate centers | Newest assignment |
|---|---|---|---|---|
| Windstream | Incumbent landline (ILEC) | 60(10%) | 55 | — |
| Verizon Wireless (Cellco Partnership) | Wireless | 46(8%) | 29 | 2024-08-27 |
| UScellular | Wireless | 39(7%) | 21 | 2025-03-21 |
| Windstream | Incumbent landline (ILEC) | 32(5%) | 25 | 2016-07-28 |
| Qwest (CenturyLink / Lumen) | Incumbent landline (ILEC) | 30(5%) | 16 | 2015-03-09 |
| Onvoy (Sinch) | Competitive / VoIP (CLEC) | 29(5%) | 29 | 2024-05-22 |
| Farmers Tel. CO. | Incumbent landline (ILEC) | 28(5%) | 5 | 2006-10-16 |
| AT&T Mobility (New Cingular Wireless PCS) | Wireless | 28(5%) | 26 | 2023-11-27 |
| Windstream | Incumbent landline (ILEC) | 28(5%) | 17 | 2019-10-21 |
| T-Mobile USA | Wireless | 23(4%) | 16 | 2025-03-20 |
| Onvoy (Sinch) | Competitive / VoIP (CLEC) | 22(4%) | 22 | 2024-03-14 |
| Winnebago Coop. Tel. Assn. | Incumbent landline (ILEC) | 18(3%) | 16 | — |
Largest rate centers (exchanges) by prefixes: Mason City (20), New Haven (17), Marshalltown (16), Ottumwa (15), New Hampton (12), Oskaloosa (12), Pella (12), Charles City (11), Newton (10), Fairfield (9). Source: NANPA Central Office Code Utilized Assignments (public, refreshed weekly).
What to do about calls from 641 numbers
Before you call back
- Debt reduction is the top named complaint here. Don't pay upfront fees for debt relief; the FTC's Telemarketing Sales Rule bans them. Talk to your lender or a nonprofit credit counselor instead. Read about debt-relief robocalls.
- Look up the full number above. A missed call from 641 with no voicemail is usually a robocall; anyone who needs you will leave a message.
- Block repeat callers: iPhone, Android, or your carrier's free filter (Verizon, AT&T, T-Mobile).
Report it in Iowa
- Unwanted sales calls and robocalls: donotcall.gov (FTC). Scams and fraud: ReportFraud.ftc.gov.
- Spoofing, texts and call-blocking problems: FCC consumer complaints.
- State complaints: Iowa Attorney General.
- Iowa does not run its own Do Not Call registry and has not formally adopted the federal list as a state list. The federal National Do Not Call Registry at donotcall.gov still applies to you — register there, free, and it never expires.
Your FTC and FCC reports are published (without your name or number) in the datasets this page is built from. How to report unwanted calls.
Area code 641: questions answered from the data
Where is area code 641?
Area code 641 serves Mason City, New Haven and Marshalltown, Iowa, covering Mitchell County, Marshall County and Cerro Gordo County and 43 more counties. It has been in service since July 9, 2000. It was split from area code 515.
What time zone is area code 641 in?
Area code 641 is in the Central time zone (UTC−6, or UTC−5 during daylight saving time). The current local time is shown at the top of this page.
What are calls from 641 numbers usually about?
Since Jul 24, consumers filed 914 FTC Do Not Call complaints about 641 numbers. The most common named subject was debt-relief pitches: 27% of complaints, 90% of them recorded messages. Across all subjects, 80% of callers who answered the question said the call was a robocall.
When do 641 spam calls happen?
31% of the complaints that give a call time describe calls between 1pm and 4pm, and 90% came on weekdays, most often on Tuesday. Times are as consumers reported them.
Are calls from 641 numbers really local?
Not necessarily. Only 36% of the FTC complaints about 641 numbers came from Iowa residents; the most came from California, Florida and Texas. 641 numbers are being used for nationwide campaigns, so the area code says little about where the caller is.
Are 641 robocalls increasing?
In the four weeks to Oct 20, consumers filed 283 FTC complaints about 641 numbers, 4% fewer than the four weeks before.
How do I report a 641 scam call in Iowa?
Report unwanted sales calls and robocalls to the FTC at donotcall.gov, and scams to ReportFraud.ftc.gov. The FCC takes complaints at consumercomplaints.fcc.gov. In Iowa, the Iowa Attorney General also handles consumer complaints about scam calls. Reports feed the public data this page is built from.
Other Iowa area codes
Sources: FTC Do Not Call complaints (unverified consumer reports), published every weekday and available here from Jul 24; FCC Consumer Complaint Data, public record, imported nightly; NANPA numbering records. A number appearing here means consumers reported calls that displayed it. Caller ID can be spoofed.