350 Area Code: Stockton, California
Area code 350 serves Stockton, Modesto and Atwater, California in the Pacific time zone, in service since 2022. Consumers have filed 188 unwanted-call complaints against 138 different 350 numbers, 34 of them with the FTC in the last 30 days. Look up the exact number that called you below.
Area code 350 at a glance
- State
- California
- Main cities
- Stockton, Modesto, Atwater, Manteca, Turlock, Tracy + 33 more
- Counties
- San Joaquin County, Stanislaus County, Merced County, Tuolumne County + 4 more
- Local time
- —Pacific
- In service since
- November 28, 2022
- Overlay of
- 209
- Local dialing
- 10 digits (area code + number)
- Exchanges
- 41 rate centers, 88 prefixes
Sources: NANPA area code and central office code records (refreshed weekly); cities and counties matched from US Census Bureau and USGS place names.
Most-reported 350 numbers
Ranked by FTC Do Not Call complaints this month, then all-time FTC and FCC complaints. Only numbers with enough complaints for a full report page are listed. Click one for what it was reported for and where.
What calls from 350 numbers are about
150 FTC Do Not Call complaints about 350 numbers since Jul 24. The most common named subject is debt-relief pitches, at 27% of complaints (90% of those were recorded messages). Overall, 79% of callers who answered said the call was a robocall.
FTC complaint subjects
- Other / unspecified4832%
- Debt reduction4127%
- Impostor (government, business, family)1913%
- Dropped call / no message149%
- No subject given128%
- Vacation & timeshares53%
- Energy, solar & utilities32%
FCC complaints by call type, last 2 years
- Prerecorded Voice643%
- Live Voice429%
- Text Message429%
29% of recent FCC complaints about 350 numbers are about text messages, not calls.
When 350 spam calls come in
35% of complaints that give a call time describe calls between 11am and 2pm. 93% came Monday to Friday, most on Fridays, 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?
36 FTC complaints about 350 numbers in the last four weeks, down 3% on the four weeks before. FCC complaints about 350 numbers peaked in 2024 (9); 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 30% of the FTC complaints about 350 numbers came from California residents; the most came from Florida, Texas and Virginia. 350 numbers are being used for nationwide campaigns, so the area code says little about where the caller is.
Where complainants live
- California4530%
- Florida128%
- Texas96%
- Virginia75%
- Ohio64%
Busiest 350 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 |
|---|---|---|---|---|
| (350) 204-xxxx | 8 | 7 | T-Mobile USA | Atwater |
| (350) 202-xxxx | 6 | 5 | Commio, LLC | Thornton |
| (350) 200-xxxx | 5 | 5 | Bandwidth.com | Lodi |
Carriers operating in 350
NANPA has assigned 88 350 prefixes (NPA-NXX central-office codes) across 41 rate centers: 28% to wireless carriers, 72% to landline and VoIP operators; 100% are pooled blocks shared by several carriers. 13 prefixes were assigned in the last 12 months (newest 2026-09-21). 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 |
|---|---|---|---|---|
| Onvoy (Sinch) | Competitive / VoIP (CLEC) | 20(23%) | 14 | 2026-08-21 |
| Onvoy (Sinch) | Competitive / VoIP (CLEC) | 17(19%) | 16 | 2026-08-04 |
| AT&T Mobility (New Cingular Wireless PCS) | Wireless | 12(14%) | 8 | 2026-04-22 |
| Commio, LLC | Competitive / VoIP (CLEC) | 7(8%) | 7 | 2023-12-21 |
| T-Mobile USA | Wireless | 7(8%) | 5 | 2025-08-20 |
| Terra Nova Telecom INC. | Competitive / VoIP (CLEC) | 7(8%) | 7 | 2022-10-04 |
| Verizon Wireless (Cellco Partnership) | Wireless | 5(6%) | 4 | 2025-05-21 |
| Comcast (Xfinity Voice) | Competitive / VoIP (CLEC) | 2(2%) | 2 | 2023-01-18 |
| Nuso, LLC | Competitive / VoIP (CLEC) | 2(2%) | 2 | 2025-04-21 |
| Teleport Communications America, LLC | Competitive / VoIP (CLEC) | 2(2%) | 2 | 2026-09-21 |
| 8x8, INC. | Competitive / VoIP (CLEC) | 1(1%) | 1 | 2026-05-20 |
| At&T Enterprises, LLC | Competitive / VoIP (CLEC) | 1(1%) | 1 | 2024-10-08 |
Largest rate centers (exchanges) by prefixes: Stockton (11), Modesto (10), Atwater (7), Manteca (5), Lodi (4), Tracy (4), Turlock (4), Clements (2), Dos Palos (2), Galt (2). Source: NANPA Central Office Code Utilized Assignments (public, refreshed weekly).
What to do about calls from 350 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 350 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 California
- 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: California Attorney General.
- California formally adopted the FTC's National Do Not Call Registry as its own state list rather than running a separate one, so a single free registration at donotcall.gov covers you. State authorities can still enforce against telemarketers who ignore it, in addition to any federal penalty.
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 350: questions answered from the data
Where is area code 350?
Area code 350 serves Stockton, Modesto and Atwater, California, covering San Joaquin County, Stanislaus County and Merced County and 5 more counties. It has been in service since November 28, 2022.
What time zone is area code 350 in?
Area code 350 is in the Pacific time zone (UTC−8, or UTC−7 during daylight saving time). The current local time is shown at the top of this page.
What are calls from 350 numbers usually about?
Since Jul 24, consumers filed 150 FTC Do Not Call complaints about 350 numbers. The most common named subject was debt-relief pitches: 27% of complaints, 90% of them recorded messages. Across all subjects, 79% of callers who answered the question said the call was a robocall.
When do 350 spam calls happen?
35% of the complaints that give a call time describe calls between 11am and 2pm, and 93% came on weekdays, most often on Friday. Times are as consumers reported them.
Are calls from 350 numbers really local?
Not necessarily. Only 30% of the FTC complaints about 350 numbers came from California residents; the most came from Florida, Texas and Virginia. 350 numbers are being used for nationwide campaigns, so the area code says little about where the caller is.
Are 350 robocalls increasing?
In the four weeks to Oct 15, consumers filed 36 FTC complaints about 350 numbers, 3% fewer than the four weeks before.
How do I report a 350 scam call in California?
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 California, the California Attorney General also handles consumer complaints about scam calls. Reports feed the public data this page is built from.
Overlay and nearby 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.