Company lists · Data refreshed September 2026

Top 25 Inside sales call centers worldwide

RevenueBase identified 2,298 company matches for inside sales call centers worldwide as of September 2026 and tracks 48,072 professional contacts across them, including 3,298 with verified work emails. The United States is the largest market and Rawalpindi the largest hub.

This list covers company matches for inside sales 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 September 28, 2026. Country and city lists for inside sales 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 Sep 28, 2026 How this list was built
2,298Companies
48,072Contacts tracked
3,298Verified emails
Explore this list → Free signup · no credit card · 500 free credits

The 25 largest inside sales call centers worldwide

Ranked by team size
Top 25 of 2,298 company matches for inside sales call centers worldwide, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Sep 28, 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.
#CompanyRevenueBase SmartSearchHeadquartersEmployeesContacts
1Exact matchBerwyn, PA, United StatesHQ recorded Sep 28, 20265,001-10,0002,774 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 · Sep 28, 2026 · View company records in RevenueBase
2Exact matchSt Petersburg, FL, RussiaHQ recorded Sep 28, 20261,001-5,0001,198 contacts →

Exact match

“The Office Gurus (TOG) is a global call center and business process outsource provider of customer care, telemarketing, lead generation, appointment setting, order entry, accounts…”

Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
3Exact matchGoiânia, BrazilHQ recorded Sep 28, 202610001+1,058 contacts →

Exact match

“Em breve uma nova página da BTCC Conexão Cliente.”

Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
4Exact matchGennevilliers Cedex, FranceHQ recorded Sep 28, 202610001+978 contacts →

Exact match

“Expert de la relation client depuis 1996, b2s est le N°1 de l’externalisation de votre relation client en qualité délivrée.”

Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
5Exact matchDoral, FL, United StatesHQ recorded Sep 28, 20261,001-5,000902 contacts →

Exact match

“Our Company Inktel is a leading business process outsourcer that specializes in creating personalized call center solutions which enable our clients to increase market share…”

Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
6Exact matchHorsham, PA, United StatesHQ recorded Sep 28, 2026501-1,000883 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 · Sep 28, 2026 · View company records in RevenueBase
7Exact matchJohannesburg, South AfricaHQ recorded Sep 28, 2026501-1,000542 contacts →

Exact match

“R683 million in annualised premium income generated for our clients, R70 billion in insurance cover sold to almost 2 million South African people, by 850 previously disadvantaged…”

Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
8Exact matchSão Paulo, BrazilHQ recorded Sep 28, 2026201-500474 contacts →

Exact match

“A HOME AGENT S.A.”

Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
9Exact matchCairo, EgyptHQ recorded Sep 28, 20261,001-5,000447 contacts →

Exact match

“Proper Business solutions is offering a comprehensive suite of customer care call center services, outbound and lead generation, back-office and data processing solutions to…”

Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
10Exact matchHurst, TX, United StatesHQ recorded Sep 28, 202651-200428 contacts →

Exact match

“Alliance is a domestically operated, internationally recognized professional contact center specializing in lead generation and appointment setting.”

Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
11Exact matchFort Worth, TX, United StatesHQ recorded Sep 28, 2026501-1,000393 contacts →

Exact match

“Touchstone Communications was built in 2002 on the philosophy of hiring educated, motivated talent and then providing them with the best training and management to achieve our…”

Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
12Exact matchSao Jose Do Rio Preto, BrazilHQ recorded Sep 28, 2026501-1,000376 contacts →

Exact match

“A Cobmax é uma Sales Center com inteligência em vendas, fruto de metodologia própria, testada e aprovada em 11 anos de experiência.”

Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
13Exact matchBloomington, MN, United StatesHQ recorded Sep 28, 20261,001-5,000354 contacts →

Exact match

“For over 35 years, The Connection has made a name for ourselves becoming one of the top industry partners to Fortune 500 companies looking to outsource their contact center…”

Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
14Exact matchIowa City, United StatesHQ recorded Sep 28, 20261,001-5,000346 contacts →

Exact match

“As a distinguished global leader in call center outsourcing, OnBrand24 takes pride in its 30-year legacy of delivering exceptional inbound and outbound call center services across…”

Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
15Exact matchTunis, TunisiaHQ recorded Sep 28, 2026501-1,000338 contacts →

Exact match

“With more than 900 employees, PhoneAct is an ISO 9001/2008 certified offshore call center service provider.”

Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
16Exact matchSacramento, CA, United StatesHQ recorded Sep 28, 2026201-500307 contacts →

Exact match

“TeleDirect provides 24/7 U.S-based call center and answering services for organizations that cannot afford to miss important calls.”

Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
17Exact matchToronto, ON, CanadaHQ recorded Sep 28, 2026501-1,000306 contacts →

Exact match

“Optima Communications International (OCI) is a Canadian contact center and business process outsourcer (BPO) specializing in regulated and complex industries, including utilities…”

Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
18Exact matchDresden, GermanyHQ recorded Sep 28, 20261,001-5,000303 contacts →

Exact match

“gevekom - Your better place to work.”

Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
19Exact matchReggio Calabria, ItalyHQ recorded Sep 28, 2026501-1,000299 contacts →

Exact match

“ACCUEIL is a leading Italian company in the field of Call Center and Business Process Outsourcing Services.”

Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
20Exact matchLos Angeles, TX, United StatesHQ recorded Sep 28, 202651-200289 contacts →

Exact match

“Current Vertical Focus: Real Estate - Lead Generation, Lead Conversion, Lead Qualification, Agent Recruiting Mortgage - Lead Conversion, Lead Qualification Insurance - Lead…”

Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
21Exact matchNew Delhi, IndiaHQ recorded Sep 28, 2026201-500284 contacts →

Exact match

“Navigant Technologies is an ISO 9001-2008 certified international call center headquartered in Delhi, India.”

Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
22Exact matchLehi, UT, United StatesHQ recorded Sep 28, 2026501-1,000256 contacts →

Exact match

“Boomsourcing (A Fusion CX Company) is a call center established in 2007.”

Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
23Exact matchDetroit, MI, United StatesHQ recorded Sep 28, 20261,001-5,000247 contacts →

Exact match

“Rocket Connections is a sales and support platform specializing in contact center services.”

Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
24Exact matchMontréal, QC, CanadaHQ recorded Sep 28, 2026201-500246 contacts →

Exact match

“Since 1995, VOXDATA has been supplying outsourced call centre services, 24 hours a day, seven days a week, to meet all frontline customer relations needs.”

Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase
25Exact matchBrighton, United KingdomHQ recorded Sep 28, 2026201-500243 contacts →

Exact match

“The Telemarketing Company is one of the UK's most trusted telemarketing agencies, delivering flexible, high-quality voice services, including pre and post sales research…”

Recorded in the RevenueBase company graph · Sep 28, 2026 · View company records in RevenueBase

Showing 25 of 2,298 inside sales call centers worldwide

See the full list, filter by size, metro and specialty, and access 3,298 tracked professional contacts with verified work emails. Direct dials are available where recorded.

Free signup · no credit card

View the full list →

Inside sales call centers worldwide at a glance

As of Sep 28, 2026
6.9%Verified-email coverage
20.9Average contacts per company
11-50Median size (employees)
2.0%Largest-city concentration · Rawalpindi
Sep 28, 2026Page data refreshed

Companies by employee count

1-10
508
11-50
797
51-200
623
201-500
213
501-1,000
96
1,001-5,000
50
5,001-10,000
2
10001+
5

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 inside sales call centers are linked below.
What qualifies
Company records worldwide whose business descriptions match “inside sales 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 3,298 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 September 28, 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.

Inside sales call centers by location

8 lists · largest first

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

Countries

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 “inside sales call centers”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many inside sales call centers are there worldwide?

RevenueBase identified 2,298 company matches for inside sales call centers worldwide as of September 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?

Advanced Call Center Technologies, LLC tops the displayed preview by professional contacts tracked in RevenueBase. Recorded headquarters appear in the company rows.

Which country has the most inside sales call centers?

The United States leads with 424 companies, followed by India (112) and the United Kingdom (90). Every inside sales call centers list by country and city is linked on this page.

Which city has the most inside sales call centers?

Rawalpindi leads with 47 company records, followed by Lahore (34) and Karachi (25).

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 3,298 professional contacts with verified work emails tracked across these 2,298 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 September 28, 2026.

Ready to reach these companies? Verified emails and direct dials for all 2,298 inside sales call centers worldwide. Start with a free account, no credit card.

Download this list →

Related lists

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.