Company lists · Data refreshed September 2026

Top 25 Sales development call centers worldwide

Name: Sales development call centers worldwide
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 29, 2026 8,602 companies tracked

RevenueBase identified 8,602 sales development call centers worldwide as of September 2026 and tracks 94,816 professional contacts across them, including 9,652 with verified work emails. The United States is the largest market and London the largest hub.

This list covers sales development call centers worldwide, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Every row shows the company's own description, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 29, 2026. Country and city lists for sales development call centers follow the table.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase Smart Search, 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 HQ checked on every row RevenueBase Smart Search rating on every row Refreshed Sep 29, 2026 86% judged on-target in blind review

8,602Companies

94,816Contacts tracked

9,652Verified emails

Explore this list → Free signup · no credit card · 500 free credits

The 25 largest sales development call centers worldwide

Ranked by team size

Top 25 of 8,602 sales development call centers worldwide, ranked by team size, largest first. Data refreshed Sep 29, 2026. RevenueBase Smart Search rates how each company's information relates to sales development call centers: strong evidence (its own description names it), partial (names part of it), indirect (matched on the rest of its profile rather than the description shown). Click a contact count to view that company's people.
#	Company	RevenueBase Smart Search	Headquarters	Employees	Contacts
1	Advanced Call Center Technologies, LLC	Strong evidence	Berwyn, PA, United StatesHQ checked Sep 29, 2026	5,001-10,000	2,774 contacts →
	Strong evidence “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…” Source: RevenueBase Database · checked Sep 29, 2026
2	The Office Gurus	Strong evidence	St Petersburg, FL, RussiaHQ checked Sep 29, 2026	1,001-5,000	1,198 contacts →
	Strong evidence “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…” Source: RevenueBase Database · checked Sep 29, 2026
3	Inktel Contact Center Solutions	Strong evidence	Doral, FL, United StatesHQ checked Sep 29, 2026	1,001-5,000	902 contacts →
	Strong evidence “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…” Source: RevenueBase Database · checked Sep 29, 2026
4	Answernet	Indirect evidence	Horsham, PA, United StatesHQ checked Sep 29, 2026	501-1,000	883 contacts →
	Indirect evidence “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!” Source: RevenueBase Database · checked Sep 29, 2026
5	Memoryblue	Indirect evidence	Tysons, VA, United StatesHQ checked Sep 29, 2026	501-1,000	825 contacts →
	Indirect evidence “memoryBlue is the go-to partner for revenue leaders in B2B Tech looking to grow their pipeline engine.” Source: RevenueBase Database · checked Sep 29, 2026
6	ZAZ Vendas	Indirect evidence	Campinas, BrazilHQ checked Sep 29, 2026	501-1,000	796 contacts →
	Indirect evidence “Em um mercado cada vez mais competitivo, onde a eficiência em vendas massificadas e externas é um desafio constante, a ZAZ Vendas surge como a resposta definitiva.” Source: RevenueBase Database · checked Sep 29, 2026
7	Abstrakt Marketing Group	Indirect evidence	St Louis, MO, United StatesHQ checked Sep 29, 2026	501-1,000	724 contacts →
	Indirect evidence “We book the qualified meetings that fill your pipeline for any B2B company ready to grow.” Source: RevenueBase Database · checked Sep 29, 2026
8	Talksure	Indirect evidence	Durban, South AfricaHQ checked Sep 29, 2026	501-1,000	718 contacts →
	Indirect evidence “Established in 2010, Talksure has developed a reputation for being a respected financial services provider and outsource business services partner.” Source: RevenueBase Database · checked Sep 29, 2026
9	Salebuild	Indirect evidence	Redwood City, CA, United StatesHQ checked Sep 29, 2026	n/a	708 contacts →
	Indirect evidence “Salesify, a leading provider of B2B demand generation services, helps our clients create pipeline and accelerate revenue by identifying, profiling, nurturing and connecting with…” Source: RevenueBase Database · checked Sep 29, 2026
10	Girnar Care	Partial evidence	Jaipur, IndiaHQ checked Sep 29, 2026	501-1,000	649 contacts →
	Partial evidence “We at Girnar Care work towards customer satisfaction and it is also a center of customer excellence.” Source: RevenueBase Database · checked Sep 29, 2026
11	Telenet Marketing Solutions	Indirect evidence	Athens, GA, IndiaHQ checked Sep 29, 2026	201-500	553 contacts →
	Indirect evidence “From initial market awareness to the final stages of a complex B2B buying journey, modern buyers crave authentic interaction.” Source: RevenueBase Database · checked Sep 29, 2026
12	O'keeffe & Swartz	Indirect evidence	Johannesburg, South AfricaHQ checked Sep 29, 2026	501-1,000	542 contacts →
	Indirect evidence “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…” Source: RevenueBase Database · checked Sep 29, 2026
13	Movingdneedle Pvt. LTD	Partial evidence	Sterling Heights, MI, United StatesHQ checked Sep 29, 2026	51-200	528 contacts →
	Partial evidence “movingDneedle is a Business to Business Sales Lead Generation Company that provides fast and scalable, sales qualified leads through its unique Personalized Email Marketing…” Source: RevenueBase Database · checked Sep 29, 2026
14	Wyzmindz Solutions Pvt. LTD	Indirect evidence	Bangalore, IndiaHQ checked Sep 29, 2026	51-200	467 contacts →
	Indirect evidence “WyzMindz Solutions Pvt.” Source: RevenueBase Database · checked Sep 29, 2026
15	Saleshive	Indirect evidence	Denver, CO, United StatesHQ checked Sep 29, 2026	51-200	455 contacts →
	Indirect evidence Source: RevenueBase Database · checked Sep 29, 2026
16	Alliance Pdms	Partial evidence	Hurst, TX, United StatesHQ checked Sep 29, 2026	51-200	428 contacts →
	Partial evidence “Alliance is a domestically operated, internationally recognized professional contact center specializing in lead generation and appointment setting.” Source: RevenueBase Database · checked Sep 29, 2026
17	Touchstone Communications	Indirect evidence	Fort Worth, TX, United StatesHQ checked Sep 29, 2026	501-1,000	393 contacts →
	Indirect evidence “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…” Source: RevenueBase Database · checked Sep 29, 2026
18	The Lead Market	Indirect evidence	Nagpur, IndiaHQ checked Sep 29, 2026	51-200	387 contacts →
	Indirect evidence “TLM empowers businesses to generate revenue through their qualified leads.” Source: RevenueBase Database · checked Sep 29, 2026
19	Voicenter S.A	Strong evidence	Cordoba, ArgentinaHQ checked Sep 29, 2026	501-1,000	384 contacts →
	Strong evidence “Nuestras soluciones de Sales Center, Contact Center y BPO están enfocadas en lograr los resultados esperados en cada proyecto que abordamos, optimizando al máximo el rendimiento…” Source: RevenueBase Database · checked Sep 29, 2026
20	Beyond Codes INC	Partial evidence	Simi Valley, CA, United StatesHQ checked Sep 29, 2026	201-500	380 contacts →
	Partial evidence “Beyond Codes is a global B2B lead generation and appointment-setting agency trusted by some of the world's leading technology companies to build enterprise sales pipeline.” Source: RevenueBase Database · checked Sep 29, 2026
21	EBQ	Partial evidence	Austin, TX, United StatesHQ checked Sep 29, 2026	201-500	377 contacts →
	Partial evidence “EBQ is an outsourced sales and marketing organization that provides services to help companies scale.” Source: RevenueBase Database · checked Sep 29, 2026
22	Cobmax	Strong evidence	Sao Jose Do Rio Preto, BrazilHQ checked Sep 29, 2026	501-1,000	376 contacts →
	Strong evidence “A Cobmax é uma Sales Center com inteligência em vendas, fruto de metodologia própria, testada e aprovada em 11 anos de experiência.” Source: RevenueBase Database · checked Sep 29, 2026
23	The Connection Contact Center	Partial evidence	Bloomington, MN, United StatesHQ checked Sep 29, 2026	1,001-5,000	354 contacts →
	Partial evidence “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…” Source: RevenueBase Database · checked Sep 29, 2026
24	FUNNL	Partial evidence	Philadelphia, United StatesHQ checked Sep 29, 2026	201-500	349 contacts →
	Partial evidence “FunnL was built on a revolutionary idea: B2B companies don’t need more leads-they need more qualified sales meetings with decision-makers.” Source: RevenueBase Database · checked Sep 29, 2026
25	Phoneact	Strong evidence	Tunis, TunisiaHQ checked Sep 29, 2026	501-1,000	338 contacts →
	Strong evidence “With more than 900 employees, PhoneAct is an ISO 9001/2008 certified offshore call center service provider.” Source: RevenueBase Database · checked Sep 29, 2026

RevenueBase Smart Search

RevenueBase Smart Search assesses information from a company’s LinkedIn profile, information supplied directly by the company, its website, and other publicly available sources. It uses that information to rate how closely the company relates to this list’s category: sales development call centers. Every row carries its rating and the description the rating was read from, so each one can be checked rather than taken on trust.

Strong evidence: The company's own public description of its business names sales development call centers.
Partial evidence: Its own public description names part of sales development call centers, so it works in or next to the category without describing itself that way.
Indirect evidence: The description shown does not name sales development call centers. The match rests on the rest of the company's public profile rather than the one sentence quoted here, so this is the rating to check first.

RevenueBase Smart Search is how these lists are built: RevenueBase's data engine and AI assemble the companies that match a category defined in a user's own words, so a list can be about what companies actually do rather than about whichever industry code they were filed under.

Showing 25 of 8,602 sales development call centers worldwide

See the full list, filter by size, metro and specialty, and get verified emails and direct dials for all 9,652 reachable decision-makers.

Free signup · no credit card

View the full list →

Sales development call centers worldwide at a glance

As of Sep 29, 2026

10.2%Verified-email coverage

11.0Average contacts per company

11-50Median size (employees)

2.3%Largest-city concentration · London

Sep 29, 2026Page data refreshed

Companies by employee count

1-10

4,191

11-50

2,769

51-200

1,167

201-500

320

501-1,000

1,001-5,000

5,001-10,000

10001+

Email recency is reported on each country list linked below.

How this list was built

Company categories are rarely black and white. RevenueBase reads each company's own description of its business to decide whether it belongs among sales development call centers, so some rows will be adjacent to the category rather than pure plays. The description and RevenueBase Smart Search rating on every row are there so you can check each match yourself.

Source: The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase Smart Search, the natural-language company search available to every RevenueBase user.
Coverage: Every country. Country and city lists for sales development call centers are linked below.
What qualifies: Companies worldwide whose own description of what they do matches “sales development call centers”. Matching reads each company's description, not its industry code or its name.
RevenueBase Smart Search: RevenueBase Smart Search is how this list is assembled and how each row is rated. RevenueBase's data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to a category defined in a user's own words. Each row is rated strong evidence (its own description names sales development call centers), partial evidence (it names part of the category) or indirect evidence (the description shown names none of it and the match rests on the rest of the company's profile). The description supporting each rating is quoted on the row.
What we exclude: Companies whose own description does not clearly place them among sales development call centers, and records with no verified work email.
Match quality: In blind human judging of this matching method, 86% of matched companies were on target. Expect roughly 1 in 7 rows to be adjacent to the category rather than a pure play. Every row shows the company's own description and its RevenueBase Smart Search rating so you can judge each match yourself. Read the full methodology: how the lists are built, how the judging worked, and what the figure means.
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 listed company carries at least one verified work email, 9,652 across the full list. 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 29, 2026. Lists refresh periodically as the graph is re-checked.
Corrections: Wrong category, wrong headquarters, or a company that has closed? Use “Report an issue” on any row. Reports go to the RevenueBase Data Team and feed back into the company graph.

Sales development call centers by location

39 lists · largest first

Every Sales development 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 Smart Search?

RevenueBase Smart Search is how RevenueBase decides which companies belong on this list and how strongly each one fits. Its data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to the category the list is about. Each row is rated strong evidence when the company's own description names sales development call centers, partial evidence when it names part of the category, and indirect evidence when the description shown names none of it and the match rests on the rest of the company's profile.

How many sales development call centers are there worldwide?

RevenueBase identified 8,602 sales development call centers worldwide as of September 2026, matched on each company's own description of what it does rather than its industry code.

What is the largest company on this list?

Advanced Call Center Technologies, LLC, headquartered in Berwyn, tops this list with the largest team on record.

Which country has the most sales development call centers?

The United States leads with 1,768 companies, followed by the United Kingdom (665) and India (628). Every sales development call centers list by country and city is linked on this page.

Which city has the most sales development call centers?

London leads with 198 headquartered companies, followed by Pune (144) and Paris (91).

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work the top results, verified emails and direct dials included. Upgrading unlocks all 9,652 verified decision-maker contacts tracked across these 8,602 companies.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 29, 2026.

Ready to reach these companies? Verified emails and direct dials for all 8,602 sales development call centers worldwide. Start with a free account, no credit card.

Download this list →

Related lists

Browse the directory

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 Smart Search, 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.