Company lists · Data refreshed October 2026

Top 25 Telecom services providers for call centers worldwide

Name: Telecom services providers for call centers worldwide
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Oct 20, 2026 9,488 companies tracked

RevenueBase identified 9,488 company matches for telecom services providers for call centers worldwide as of October 2026 and tracks 173,809 professional contacts across them, including 30,304 with verified work emails. The United States is the largest market and London the largest hub.

This list covers company matches for telecom services providers for call centers worldwide, found by RevenueBase SmartSearch using the meaning of business descriptions in its company graph at Exact. Ranked by professionals tracked, largest first. Rows show recorded descriptions where available, Exact search membership and the snapshot date. Data refreshed October 20, 2026. Country and city lists for telecom services providers for call centers follow the table.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase SmartSearch, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.

How to read this list RevenueBase SmartSearch · Exact Recorded Oct 20, 2026 How this list was built

9,488Companies

173,809Contacts tracked

30,304Verified emails

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The 25 largest telecom services providers for call centers worldwide

Ranked by team size

Top 25 of 9,488 company matches for telecom services providers for call centers worldwide, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Oct 20, 2026. The RevenueBase SmartSearch column shows Exact match membership in this saved search. Click a contact count to view that company's people. Totals use company locations recorded by RevenueBase; the displayed preview is a smaller selection.
#	Company	RevenueBase SmartSearch	Headquarters	Employees	Contacts
1	Windstream	Exact match	Little Rock, AR, United StatesHQ recorded Oct 20, 2026	10001+	7,474 contacts →
	Exact match “Windstream and Uniti have merged - Please follow us at Uniti Group, Inc.” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
2	Cable ONE	Exact match	Phoenix, AZ, United StatesHQ recorded Oct 20, 2026	1,001-5,000	5,785 contacts →
	Exact match “Cable One Business offers scalable, reliable, and efficient solutions so that the businesses we serve can be successful.” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
3	Spectrum Business	Exact match	Stamford, CT, United StatesHQ recorded Oct 20, 2026	10001+	4,046 contacts →
	Exact match “Our story starts with understanding that connectivity powers everything you do, and we make it stronger.” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
4	Advanced Call Center Technologies, LLC	Exact match	Berwyn, PA, United StatesHQ recorded Oct 20, 2026	5,001-10,000	2,997 contacts →
	Exact match “Advanced Call Center Technologies, LLC (ACT) is a premier provider of domestic (USA), near shore and far shore outsourced call center services to the financial services, mortgage…” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
5	Airtel Business	Exact match	Gurgaon, IndiaHQ recorded Oct 20, 2026	10001+	2,747 contacts →
	Exact match “The B2B arm of Bharti Airtel, we are India's leading provider of secure and reliable connectivity, technology, and communications solutions.” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
6	Granite Telecommunications	Exact match	Quincy, MA, United StatesHQ recorded Oct 20, 2026	1,001-5,000	2,346 contacts →
	Exact match “Granite is a dynamic and rapidly growing company serving the exciting and demanding Telecommunications market.” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
7	Unifique	Exact match	Timbó, BrazilHQ recorded Oct 20, 2026	1,001-5,000	1,920 contacts →
	Exact match “Somos uma empresa de telecomunicações com 28 anos de atuação.” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
8	GAMMA	Exact match	London, United KingdomHQ recorded Oct 20, 2026	1,001-5,000	1,624 contacts →
	Exact match “Gamma Communications is a leading provider of technology-based communication solutions across Europe.” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
9	Integra	Exact match	Vancouver, WA, United StatesHQ recorded Oct 20, 2026	501-1,000	1,201 contacts →
	Exact match “Integra is Allstream.” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
10	Hawaiian Telcom	Exact match	Honolulu, HI, United StatesHQ recorded Oct 20, 2026	1,001-5,000	1,157 contacts →
	Exact match “Over the last two decades our mission has evolved dramatically.” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
11	XO Communications	Exact match	Herndon, VA, United StatesHQ recorded Oct 20, 2026	1,001-5,000	1,086 contacts →
	Exact match “XO Communications is a Verizon company that provides the technology that helps business and wholesale customers compete in a hyper-connected economy.” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
12	Sercomtel	Exact match	Londrina, BrazilHQ recorded Oct 20, 2026	501-1,000	1,023 contacts →
	Exact match “A Sercomtel é a empresa paranaense de telecomunicações que oferece soluções completas em telefonia.” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
13	Youtility Center DO Brasil	Exact match	Barra Mansa, BrazilHQ recorded Oct 20, 2026	1,001-5,000	963 contacts →
	Exact match “A Youtility Center do Brasil faz parte do “Gruppo Distribuzione Spa”, com sede na Itália desde 1998.” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
14	Answernet	Exact match	Horsham, PA, United StatesHQ recorded Oct 20, 2026	501-1,000	926 contacts →
	Exact match “If you are interested in growing your business or increasing efficiency, AnswerNet has the expertise, technology, and people to help you take your company to new heights!” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
15	Mundivox Communications	Exact match	São Paulo, BrazilHQ recorded Oct 20, 2026	501-1,000	887 contacts →
	Exact match “Com mais de 25 anos de experiência, a Mundivox é uma operadora licenciada pela Anatel, especializada em soluções integradas de comunicação para o mercado corporativo.” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
16	Bestel	Exact match	Nápoles, ItalyHQ recorded Oct 20, 2026	501-1,000	829 contacts →
	Exact match “Somos un equipo de expertos en Telecomunicaciones y Tecnologías de Información.” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
17	Asiatech CO	Exact match	Tehran, IranHQ recorded Oct 20, 2026	501-1,000	805 contacts →
	Exact match “Data Transmission company of Asiatech (#asiatech) was established in 2003 to provide IT-based services and obtained PAP license from the Communications Regulatory Authority (CRA)…” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
18	Adista	Exact match	Maxéville, FranceHQ recorded Oct 20, 2026	501-1,000	746 contacts →
	Exact match “Adista, Opérateur de Services Hébergés, s'est imposé en quelques années comme le spécialiste des services informatiques proposés aux PME et Collectivités sur les réseaux très haut…” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
19	BPO Business Process Outsourcing	Exact match	Doha, QatarHQ recorded Oct 20, 2026	501-1,000	697 contacts →
	Exact match “BPO+ is a leading provider of World-class Contact Center, BPO services, Telecom System Integration and IT services in the Middle-East.” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
20	Onecom	Exact match	Fareham, United KingdomHQ recorded Oct 20, 2026	501-1,000	693 contacts →
	Exact match “Onecom is the UK’s leading business telecoms and cloud communications provider managing over a million services for business customers - delivering communication services and…” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
21	VIS Networks	Exact match	Bangalore, IndiaHQ recorded Oct 20, 2026	201-500	675 contacts →
	Exact match “We @ VIS Networks (Voice Infrastructure Services) believe in the future of technology services.” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
22	Cloud5 Communications	Exact match	Chicago, IL, United StatesHQ recorded Oct 20, 2026	501-1,000	624 contacts →
	Exact match “Leading brands, including over hotels, trust Cloud5 to deliver exceptional experiences that both attract and retain customers.” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
23	Transcosmos Malaysia	Exact match	Kuala Lumpur, MalaysiaHQ recorded Oct 20, 2026	1,001-5,000	580 contacts →
	Exact match “Transcosmos Malaysia offer integrated call center services such as Call Center, Social Media Management, Voice Of Customer Analysis, Digital Marketing and eCommerce Solution that…” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
24	DDS Telecomunicações Ltda	Exact match	São Paulo, BrazilHQ recorded Oct 20, 2026	51-200	544 contacts →
	Exact match “A DDS é uma empresa de tecnologia especializada na integração de sistemas.” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase
25	Home Agent	Exact match	São Paulo, BrazilHQ recorded Oct 20, 2026	201-500	538 contacts →
	Exact match “A HOME AGENT S.A.” Recorded in the RevenueBase company graph · Oct 20, 2026 · View company records in RevenueBase

RevenueBase SmartSearch

Describe a niche business in your own words. RevenueBase SmartSearch compares the meaning of your description with company business descriptions compiled in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit.

This list uses Exact for “telecom services providers for call centers”. Each Exact match badge shows membership in that saved search; it is not an individual similarity score or a service-quality rating. Recorded descriptions are shown where available.

Showing 25 of 9,488 telecom services providers for call centers worldwide

See the full list, filter by size, metro and specialty, and access 30,304 tracked professional contacts with verified work emails. Direct dials are available where recorded.

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Telecom services providers for call centers worldwide at a glance

As of Oct 20, 2026

17.4%Verified-email coverage

18.3Average contacts per company

11-50Median size (employees)

1.6%Largest-city concentration · London

Oct 20, 2026Page data refreshed

Companies by employee count

1-10

3,941

11-50

3,776

51-200

1,207

201-500

303

501-1,000

133

1,001-5,000

5,001-10,000

10001+

Email recency is reported on each country list linked below.

How this list was built

The recorded descriptions help you assess these company matches. Check a company’s website for its current services and locations.

Source: The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase SmartSearch, the natural-language company search available to every RevenueBase user.
Coverage: Every country. Country and city lists for telecom services providers for call centers are linked below.
What qualifies: Company records worldwide whose business descriptions match “telecom services providers for call centers” by meaning at the Exact setting. Descriptions are compiled in the RevenueBase company graph from public websites, profiles and company information where available; they are not guaranteed quotations from the company's website.
RevenueBase SmartSearch: Describe a niche company in your own words to find businesses by meaning. Exact, Similar, Related and Broad control the breadth of RevenueBase SmartSearch. This saved list uses Exact. Each row's Exact match badge shows inclusion in that search, not an individual score or a service-quality judgment.
Public preview: The public preview omits records without a verified work email. Dataset totals and geographic summaries describe the full matched records before these preview filters.
Match quality: RevenueBase's August 25, 2026 study assessed 4,198 description/company pairs across matching settings. The publisher reports 86% good or better at Exact. This evaluates the method across queries; it does not audit this individual list. Recorded company descriptions, where available, help you judge each match yourself. Read the full methodology: how the lists are built and what the study measures.
Ranking: Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
Verification: Every displayed company carries at least one verified work email. RevenueBase tracks 30,304 professional contacts with verified work emails across the full matched dataset. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
Refresh: This page's figures were pulled from the company graph on October 20, 2026. Lists refresh periodically as the graph is re-checked.
Record context: Company records and descriptions can change. Check the company's website for its current services and locations.

Telecom services providers for call centers by location

52 lists · largest first

Every Telecom services providers for call centers list RevenueBase publishes, by country and city. Counts are matching companies in each list as of its own refresh date.

Countries

Cities

Frequently asked

What is RevenueBase SmartSearch?

RevenueBase SmartSearch finds niche companies by the meaning of their business descriptions in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit your description. This list uses Exact for “telecom services providers for call centers”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many telecom services providers for call centers are there worldwide?

RevenueBase identified 9,488 company matches for telecom services providers for call centers worldwide as of October 2026, using the meaning of business descriptions at Exact. This is the recorded matched set in the RevenueBase company graph.

What is the largest company on this list?

Windstream tops the displayed preview by professional contacts tracked in RevenueBase. Recorded headquarters appear in the company rows.

Which country has the most telecom services providers for call centers?

The United States leads with 2,035 companies, followed by the United Kingdom (918) and Brazil (674). Every telecom services providers for call centers list by country and city is linked on this page.

Which city has the most telecom services providers for call centers?

London leads with 152 company records, followed by Sao Paulo (152) and New York (61).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work limited free results with 500 credits to start. Upgrading provides access to the 30,304 professional contacts with verified work emails tracked across these 9,488 companies; direct dials are available where recorded.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on October 20, 2026.

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About this data

RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase SmartSearch, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.