CallataGuidesGet a local business phone number in San Mateo, CA
San Mateo's area code, prefixes and carriers from NANPA records, and how to put a San Mateo number in front of your customers.
- Area code
- 650
- Exchanges
- 126NANPA-assigned
- Carriers
- 20
- Population
- 103,006Census 2024 est.
Area codes in San Mateo
San Mateo, in San Mateo County, California, had a Census-estimated population of 103,006 in July 2024. All 126 exchanges NANPA lists for its rate center are in area code 650. San Mateo is in the Pacific time zone.
According to NANPA's dialing-plan data, local calls within 650 are dialed as 1 plus ten digits and toll calls as 1 plus ten digits.
| Area code | Exchanges here | Share | In service since | Overlay with | Time zone |
|---|---|---|---|---|---|
| 650 | 126 | 100% | 1997 | none | Pacific |
Source: NANPA utilized central office code file and NPA report, dated 10/01/2026.
Phone carriers in San Mateo
20 carriers hold the 126 exchanges assigned to San Mateo's rate center. Pacific Bell has the most, with 49. 79 of them are pooled codes, which the holder shares with other carriers in blocks of 1,000 numbers. Holding a code means NANPA assigned that block of numbers to the carrier for this rate center; individual numbers may since have been ported elsewhere.
| Carrier (NANPA operating company) | Exchanges | Share |
|---|---|---|
| Pacific Bell | 49 | 39% |
| New Cingular Wireless PCS, LLC | 18 | 14% |
| T-mobile USA, INC. | 15 | 12% |
| Cellco Partnership d/b/a Verizon Wireless - CA | 7 | 5.6% |
| Onvoy, LLC - CA | 6 | 4.8% |
| Mcimetro Access Transmission Services LLC | 5 | 4.0% |
| Level 3 Communications, LLC - CA | 5 | 4.0% |
| Bandwidth.com CLEC, LLC - CA | 3 | 2.4% |
| Fractel, LLC | 3 | 2.4% |
| Spok, INC. | 2 | 1.6% |
| U.s. Telepacific Corp. d/b/a TPX Communications | 2 | 1.6% |
| Metropcs, INC. | 2 | 1.6% |
Carrier names are the operating company (OCN) names on NANPA's utilized central office code file dated 10/01/2026. A carrier holding a code may port numbers to other carriers.
Exchanges (NPA-NXX) assigned in San Mateo
These are the central office codes NANPA records for San Mateo. A caller seeing one of them recognizes a local number. The earliest assignment date recorded in the file for these codes is 2001. 9 of the 126 were assigned in 2020 or later.
| Area code | Prefixes (NXX) |
|---|---|
| 650 | 200, 202, 212, 217, 218, 222, 227, 235, 240, 242, 245, 274, 281, 286, 287, 288, 292, 293, 294, 295, 312, 315, 340, 341, 342, 343, 344, 345, 346, 347, 348, 349, 350, 356, 357, 358, 371, 372, 373, 375, 376, 377, 378, 389, 393, 398, 401, 403, 418, 425, 430, 431, 432, 435, 436, 437, 445, 458, 477, 483, 484, 504, 513, 514, 520, 522, 523, 524, 525, 532, 533, 539, 541, 544, 548, 554, 558, 570, 571, 572, 573, 574, 576, 577, 578, 579, 581, 612, 619, 627, 629, 638, 639, 642, 645, 650, 653, 655, 659, 667, 678, 685, 696, 699, 703, 706, 715, 727, 740, 753, 759, 762, 766, 773, 778, 781, 787, 844, 863, 865, 867, 888, 918, 921, 931, 954 |
Source: NANPA utilized central office code file.
When San Mateo's exchanges were assigned
Assignment dates show when each block of San Mateo numbers was added to the local supply.
| Decade assigned | Exchanges | Share |
|---|---|---|
| 2000s | 3 | 12% |
| 2010s | 14 | 54% |
| 2020s | 9 | 35% |
Assignment dates as recorded in NANPA's utilized code file; codes without a recorded date are excluded.
How local numbers work in San Mateo
NANPA ties every exchange to a rate center. For San Mateo that is SAN MATEO, so a number from one of these exchanges reads as local to people in and around San Mateo.
If your business already has a San Mateo number, porting it to Callata is free and keeps it on your cards, listings and vehicles.
The local business market
San Mateo is part of the San Francisco-Oakland-Fremont, CA metro area, home to 4.6 million people in 2024. County Business Patterns counted 133,246 business establishments in the San Francisco, CA metro area in 2023, employing 2,417,363 people. The largest sectors by establishment count are professional, scientific, and technical services (23,140), health care and social assistance (16,920), and accommodation and food services (13,736).
| Industry | Establishments | Employees | Employees per establishment |
|---|---|---|---|
| Full-service restaurants | 5,136 | 86,434 | 16.8 |
| Limited-service restaurants | 4,140 | 59,849 | 14.5 |
| Dental offices | 3,029 | 19,225 | 6.3 |
| Offices of real estate agents and brokers | 2,990 | 10,454 | 3.5 |
| Law offices | 2,984 | 25,802 | 8.6 |
| Custom computer programming services firms | 2,959 | 58,995 | 19.9 |
| Residential remodelers | 2,924 | 14,184 | 4.9 |
| Management consulting firms | 2,756 | 16,952 | 6.2 |
Selected small-business industries (six-digit NAICS) covered by these guides. Source: Census County Business Patterns 2023.
Business phone service in San Mateo
For $99 a month, Callata puts a team of up to 5 on one plan ($20 for each person after that): up to 3 local numbers, unlimited inbound calls, a pooled allowance of 1,500 outbound US and Canada minutes per user, browser and cell calling, voicemail transcription with urgency triage, recorded calls with AI summaries and business-hours routing, with E911 on every number.
If you already have a number in San Mateo, porting it to Callata is free. Texting from a local number requires a one-time carrier registration (10DLC, $49), and the numbers available in any area code depend on carrier inventory when you choose them.
Optional AI agents (receptionist, sales, support or scheduler) can answer calls after hours or when nobody picks up, take messages, text, email and transfer to your team. They are billed from prepaid AI minutes at $0.25 per minute, identify themselves as AI, and may only place outbound calls to people who consented, between 8am and 9pm.
An 18-person team is the benchmark here, the rounded average establishment size in the San Francisco, CA metro area. Billed per seat at month-to-month list prices (checked September 28, 2026), RingCentral RingEX Core costs $540.00 a month and Ooma Office Pro $449.10. On Callata the same 18 people cost $359.00 a month, less than either per-seat plan.
| Provider (plan) | Pricing basis | Per month | Per year |
|---|---|---|---|
| Callata (Callata Office) | $99 incl. 5 users, $20 per extra user | $359.00 | $4,308.00 |
| Quo (Starter) | $19.00 per user | $342.00 | $4,104.00 |
| Nextiva (Core) | $23.00 per user | $414.00 | $4,968.00 |
| Ooma (Office Pro) | $24.95 per user | $449.10 | $5,389.20 |
| Dialpad (Standard) | $27.00 per user | $486.00 | $5,832.00 |
| RingCentral (RingEX Core) | $30.00 per user | $540.00 | $6,480.00 |
Competitor prices are each vendor's published month-to-month list price per user for its lowest plan that includes business calling and texting, checked September 28, 2026: Quo Starter $19, Nextiva Core $23, Ooma Office Pro $24.95 (Essentials excludes texting; one-time $29.95 activation not included), Dialpad Standard $27, RingCentral RingEX Core $30 ($20 billed annually). Prices exclude taxes and fees and may change; annual contracts lower some competitors' prices.
Frequently asked questions
What area code is San Mateo, CA?
650. All exchanges NANPA lists for San Mateo are in 650.
How many phone companies have exchanges in San Mateo?
20, holding 126 exchanges between them, according to NANPA's 10/01/2026 file.
Can I keep my existing San Mateo business number?
Yes. Porting an existing number to Callata is free. Texting from it starts after carrier registration (10DLC), a one-time $49 fee.
How much is a business phone line in San Mateo?
Callata is $99 a month with 5 users included, then $20 per additional user, with up to 3 local numbers; 18 users come to $359.00 a month. For comparison, 18 users on RingCentral RingEX Core list at $540.00 a month (checked September 28, 2026).