50 leading Telecommunications companies in California (2026 list)

These California-based telecommunications companies are primarily mid-sized to large firms, with a focus on connectivity solutions, network infrastructure, and communication technologies. Companies like Viasat offer global connectivity for diverse sectors, while Pearce Services specializes in critical infrastructure maintenance. Poly provides premium audio and video products, and Sonic is a prominent ISP known for customer care.

Several companies, including Polycom, Infinera, Harmonic, and UTStarcom, are headquartered in San Jose, indicating a concentration of telecommunications expertise in the Silicon Valley area. This geographic clustering suggests a shared ecosystem for innovation and development in telecommunications solutions.

#	Company	Industry	Headquarters	Employees	Founded
1	Viasat viasat.com Global communications company providing connectivity solutions for consumers, businesses, governments, and militaries worldwide, ensuring internet access in remote locations and on-the-go	Telecommunications	🇺🇸 Carlsbad	6,809	1986
2	Poly poly.com This company provides premium audio and video products as part of HP's hybrid work solutions for optimal meetings anytime, anywhere	Telecommunications	🇺🇸 Santa Cruz	3,136	n/a
3	Pearce Services pearce-services.com Provider of repair, maintenance, and engineering services for critical infrastructure in renewable energy, power generation, and telecom industries, with tech-enabled solutions nationwide	Telecommunications	🇺🇸 Paso Robles	2,961	n/a
4	Sonic sonic.com A leading ISP in California providing fast, reliable internet and phone service for businesses and homes since 1994 Known for prioritizing customer care and online privacy rights	Telecommunications	🇺🇸 Santa Rosa	2,751	1994
5	Polycom hp.com Poly offers a range of smart communication endpoints, cloud software, and services to facilitate authentic human connection and collaboration	Telecommunications	🇺🇸 San Jose	2,008	1990
6	Mobileum mobileum.com A leading provider of telecom analytics and testing solutions for roaming, security, risk management to increase revenues, improve network security, and reduce costs	Telecommunications	🇺🇸 Cupertino	1,970	n/a
7	Infinera nokia.com Revolutionizing telecommunications networks worldwide with innovative connectivity solutions, advanced optical technology, automation software, and professional services for global customers	Telecommunications	🇺🇸 San Jose	1,960	2000
8	Spirent Communications spirent.com Provide innovative testing, assurance, and automation solutions for wireless, positioning, 5G, cloud, and autonomous vehicle technologies.	Telecommunications	🇺🇸 Santa Clara	1,755	1936
9	Finisar Corporation coherent.com Follow us at the provided link for updates and information about our rebranding as Coherent Corp Exciting changes ahead!	Telecommunications	🇺🇸 Sunnyvale	1,709	n/a
10	Harmonic harmonicinc.com Industry leader in video, broadband, and media solutions Specializing in cloud streaming, software as a service, and enabling content delivery to all screens	Telecommunications	🇺🇸 San Jose	1,612	n/a
11	UTStarcom utstar.com A telecommunications solutions company providing cutting-edge packet optical transport, broadband access, and Software Defined Networking platform to simplify network operations and boost efficiency	Telecommunications	🇺🇸 San Jose	1,252	n/a
12	Plantronics hp.com A global leader in audio communications, specializing in simple and clear communication solutions for business and consumers, promoting distraction-free environments	Telecommunications	🇺🇸 Santa Cruz	1,070	1961
13	Webex webex.com cloud-based collaboration solutions including video meetings, calling, messaging, events, customer experience, AI-driven, secure, integrated with business apps	Telecommunications	🇺🇸 San Jose	965	n/a
14	Kyocera Mobile kyoceramobile.com A leader in rugged mobility solutions, specializing in waterproof and durable mobile devices with enterprise-grade security and white glove services for business customers	Telecommunications	🇺🇸 San Diego	924	2000
15	Anuvu anuvu.com The company offers technology solutions for entertainment and connectivity in mobility markets, catering to passengers' ever-changing needs with reliable, scalable, and affordable services	Telecommunications	🇺🇸 Santa Ana	916	n/a
16	Breezeline breezeline.com A socially responsible company offering Internet, TV, and Voice services with a focus on exceptional customer service and promoting diversity	Telecommunications	🇺🇸 Quincy	885	n/a
17	Telecom Technology Services, Inc.linkedin.com Specializing in accelerating 5G network rollouts, this company automates and streamlines processes for vRAN, Open RAN, Fiber, and IoT deployment	Telecommunications	🇺🇸 Pleasanton	684	1997
18	Ooma, Inc.ooma.com The company creates innovative communications solutions for businesses and consumers, offering cloud-based telephony, home security, HD voice quality, mobile integration, and smart connected devices	Telecommunications	🇺🇸 Sunnyvale	652	2003
19	TelePacific Communications (TPx Communications)tpx.com TelePacific company is now TPx Communications, providing news and updates on their services Visit their LinkedIn page for more information	Telecommunications	🇺🇸 Los Angeles	616	1998
20	OCLARO lumentum.com A photonics company offering a best-in-class portfolio, now part of Lumentum Follow them for more information on their products	Telecommunications	🇺🇸 San Jose	606	2009
21	CHi crouching-hippo.com Specializes in providing customized software solutions for wireless telecoms industry, focusing on driving value from drive test data for big operators and equipment vendors worldwide	Telecommunications	🇺🇸 Alameda	584	2009
22	Metro Pcs Authorized Dealer metrobyt-mobile.com A telecommunications company in Tracy, California, specializing in Metro PCS services and products	Telecommunications	🇺🇸 Tracy	523	n/a
23	Tarana Wireless taranawireless.com Innovative technology company accelerating global internet access deployment with next-generation fixed wireless technology for affordable high-speed connectivity	Telecommunications	🇺🇸 Milpitas	517	2009
24	Ansafone Contact Centers ansafone.com Leading contact center with omni-channel services for US and Canadian companies, offering inbound/outbound call platforms, live chat, email, social media management, and CRM solutions	Telecommunications	🇺🇸 Santa Ana	497	1970
25	BORQS borqs.com Global leader in IoT solutions, offering customizable Android-based devices and E2E cloud services Specializing in connected solutions and MVNO services with key partnerships and industry recognition	Telecommunications	🇺🇸 Suite 320 Santa Clara	493	2007
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26	Plume plume.com Cloud-managed Wi-Fi platform offering AI-driven optimization, security, smart home services, and analytics to improve ISP customer experiences.	Telecommunications	🇺🇸 Palo Alto	474	2015
27	Source Photonics sourcephotonics.com Innovative global provider of technology for communications, data connectivity, FTTx networks, wireless connectivity, and data centers with a focus on quality and customer satisfaction	Telecommunications	🇺🇸 West Hills	447	1988
28	TruConnect truconnect.com TruConnect offers affordable prepaid and Lifeline wireless services nationwide, simplifying communication and providing flexibility to customers	Telecommunications	🇺🇸 Los Angeles	433	2011
29	Marketing Solutions SRE linkedin.com The company provides marketing solutions with a focus on generating revenue Their slogan emphasizes the importance of making money	Telecommunications	🇺🇸 Mountain View	433	2019
30	Coolpad coolpad.com Global mobile device brand focused on affordable, reliable products with user-centric innovation Offering cost-efficient, powerful, and stylish technology backed by AI	Telecommunications	🇺🇸 Irvine	428	1993
31	DASAN Zhone Solutions dasanzhone.com Global leader in network access solutions for service provider and enterprise networks, offering broadband access, Ethernet switching, Passive Optical LAN, and software-defined networks worldwide	Telecommunications	🇺🇸 Oakland	420	1999
32	Inseego Corp inseego.com Industry pioneer in smart device-to-cloud solutions, extending 5G network edge for broader coverage, high-speed data, low latency, and secure internet access worldwide	Telecommunications	🇺🇸 San Diego	413	1996
33	TeleDirect Call Centers teledirect.com TeleDirect offers on-demand contact center solutions with online tools for scripting, reporting, and lead delivery, along with consultation and services for call centers	Telecommunications	🇺🇸 Sacramento	376	1961
34	NeoPhotonics lumentum.com Specializing in accelerating optical network speed and scalability through the acquisition of NeoPhotonics products and updates under their new handle	Telecommunications	🇺🇸 San Jose	375	n/a
35	Mint Mobile careers.t-mobile.com Provides nationwide premium wireless service at low prices by eliminating overhead and passing savings directly to customers with innovation.	Telecommunications	🇺🇸 Costa Mesa	355	2016
36	Aurora Networks commscope.com Innovator of advanced optical transport and access systems for broadband networks, enabling providers to deliver capacity, flexibility, and high-capacity services	Telecommunications	🇺🇸 San Jose	353	1999
37	Faurecia intentionis.com A technology company founded in Silicon Valley in 2009, connecting devices to the cloud via intelligent software for optimized sensor traffic and privacy management	Telecommunications	🇺🇸 El Cerrito	349	2009
38	ITC Service Group callitc.com Provider of qualified personnel and managed services for planning, design, construction, and maintenance of wireless and wireline communications networks globally	Telecommunications	🇺🇸 Citrus Heights	331	1999
39	Silvus Technologies silvustechnologies.com Silvus Technologies develops advanced communication technologies reshaping tactical wireless communications with Mobile Networked MIMO technology for reliable connectivity in challenging environments	Telecommunications	🇺🇸 Los Angeles	325	2004
40	Flash Mobile A telecommunications company based in Santa Ana, California, specialized in mobile services and products	Telecommunications	🇺🇸 Santa Ana	324	n/a
41	Speakeasy speakeasy.net A company formed in 2010 through the merger of three companies, offering nationwide IP voice, security, VPN, and Internet services Acquired in 2018	Telecommunications	🇺🇸 Costa Mesa	323	1996
42	HP Communications, Inc.hpcomminc.com A full turnkey OSP/ISP contractor with over 20 years of experience, providing cutting-edge communication solutions and excellent customer service nationwide	Telecommunications	🇺🇸 Corona	320	1998
43	APWireless Infrastructure Partners, LLC apwip.com Global telecom and digital infrastructure investment company acquiring and managing critical telecom infrastructure like cell site leases, fiber, DAS, and data centers Building towers worldwide	Telecommunications	🇺🇸 San Diego	316	2010
44	Ultra Mobile ultra.me wireless telecom company offering nationwide and global calling services with focus on technology, product improvement, and customer experience	Telecommunications	🇺🇸 Costa Mesa	312	2011
45	Halo halotechnology.com A global leader in fiber optics, Halo shapes the future with compatible transceiver technology, offering innovative product solutions through its leading global brands	Telecommunications	🇺🇸 Tustin	307	n/a
46	Futurewei Technologies, Inc.futurewei.com A technology company founded in 2001 that focuses on open innovation, collaboration with companies worldwide, engagement in standard programs, and building open ecosystems	Telecommunications	🇺🇸 Santa Clara	307	2001
47	Skylite Corporation skylite.com A trusted seller of Ethernet cables since 1996, offering Cat5e/Cat6 cables at competitive prices with free shipping Also provides various low voltage cables	Telecommunications	🇺🇸 Fremont	303	1994
48	Viasat Energy Services viasat.com A trusted partner for energy industries, providing connectivity, security, and intelligence from distributed sites and assets worldwide Visit energyviasatcom for more information	Telecommunications	🇺🇸 Carlsbad	252	2001
49	Orange Liberia orange.com.lr Leading provider of telecommunications services in Liberia, offering a wide range of communication solutions to meet the needs of customers	Telecommunications	🇺🇸 Monrovia	246	n/a
50	Oplink Communications, LLC molex.com A provider of optical communication components, modules, and subsystems offering advanced solutions in DWDM, CWDM, optical amplification, switching, connectivity, and transceivers globally	Telecommunications	🇺🇸 Fremont	244	n/a

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Every company on this list has a Tamtam company profile. The industry is the one the company gives on LinkedIn; categories such as SaaS or fintech are classified by Tamtam's AI from the company's website and LinkedIn page; and the headquarters city must match the company's own address. Companies are ranked by the number of employees on LinkedIn, and the list is refreshed every night. Classifications can be wrong, so treat the list as a starting point rather than an official ranking. Last updated Nov 12, 2026.

50 leading Telecommunications companies in California

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