Company lists · Data refreshed September 2026

Top 25 Legacy system modernization companies based in the United States

Name: Legacy system modernization companies based in the United States
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 20, 2026 5,200 companies tracked

RevenueBase identified 5,200 legacy system modernization companies headquartered in the United States as of September 2026 and tracks 513,629 professional contacts across them, including 156,060 with verified work emails. New York is the largest hub.

This list covers legacy system modernization companies headquartered in the United States, 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 20, 2026.

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 20, 2026 86% judged on-target in blind review

5,200Companies

513,629Contacts tracked

156,060Verified emails

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The 25 largest legacy system modernization companies based in the United States

Ranked by team size

Top 25 of 5,200 legacy system modernization companies based in the United States, ranked by team size, largest first. Data refreshed Sep 20, 2026. RevenueBase Smart Search rates how each company's information relates to legacy system modernization companies: 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	DXC Technology	Partial evidence	Ashburn, VA, United StatesHQ checked Sep 20, 2026	10001+	82,768 contacts →
	Partial evidence “DXC Technology helps global companies run their mission-critical systems and operations while modernizing IT, optimizing data architectures, and ensuring security and scalability…” Source: RevenueBase Database · checked Sep 20, 2026
2	Epam Systems	Indirect evidence	Newtown, PA, United StatesHQ checked Sep 20, 2026	10001+	60,211 contacts →
	Indirect evidence “EPAM (NYSE:EPAM) is a global leader in AI transformation engineering and integrated consulting, serving Forbes Global companies and ambitious startups.” Source: RevenueBase Database · checked Sep 20, 2026
3	UST	Indirect evidence	Aliso Viejo, CA, United StatesHQ checked Sep 20, 2026	10001+	34,875 contacts →
	Indirect evidence “UST is a global digital transformation solutions provider.” Source: RevenueBase Database · checked Sep 20, 2026
4	Teksystems	Indirect evidence	Hanover, MD, United StatesHQ checked Sep 20, 2026	10001+	24,693 contacts →
	Indirect evidence “We’re TEKsystems and TEKsystems Global Services.” Source: RevenueBase Database · checked Sep 20, 2026
5	Insight	Indirect evidence	Chandler, AZ, United StatesHQ checked Sep 20, 2026	10001+	12,899 contacts →
	Indirect evidence “Insight Enterprises, Inc.” Source: RevenueBase Database · checked Sep 20, 2026
6	Yash Technologies	Indirect evidence	East Moline, IL, United StatesHQ checked Sep 20, 2026	5,001-10,000	7,769 contacts →
	Indirect evidence “YASH Technologies is a consulting-led transformation partner with a proven track record of helping customers address their current and prospective digital transformation…” Source: RevenueBase Database · checked Sep 20, 2026
7	R Systems	Indirect evidence	El Dorado Hills, CA, United StatesHQ checked Sep 20, 2026	5,001-10,000	7,360 contacts →
	Indirect evidence “RSI is a trusted software engineering and digital transformation services partner to global enterprises navigating technological change.” Source: RevenueBase Database · checked Sep 20, 2026
8	Aricent	Indirect evidence	Santa Clara, CA, United StatesHQ checked Sep 20, 2026	10001+	4,302 contacts →
	Indirect evidence “Aricent is now Altran, delivering industry innovations at future speed.” Source: RevenueBase Database · checked Sep 20, 2026
9	Presidio	Indirect evidence	New York, NY, United StatesHQ checked Sep 20, 2026	1,001-5,000	3,798 contacts →
	Indirect evidence “At Presidio, speed and quality meet technology and innovation.” Source: RevenueBase Database · checked Sep 20, 2026
10	Apexon	Indirect evidence	Santa Clara, CA, United StatesHQ checked Sep 20, 2026	5,001-10,000	3,532 contacts →
	Indirect evidence “Apexon is a technology services firm specializing in accelerating business transformation and engineering intelligent enterprises.” Source: RevenueBase Database · checked Sep 20, 2026
11	CES	Partial evidence	Bolingbrook, IL, United StatesHQ checked Sep 20, 2026	1,001-5,000	3,502 contacts →
	Partial evidence “CES is a trusted global provider of Technology and Business Process Modernization (BPM) services, serving enterprise clients for over three decades.” Source: RevenueBase Database · checked Sep 20, 2026
12	Iris Software INC	Indirect evidence	Edison, NJ, United StatesHQ checked Sep 20, 2026	1,001-5,000	3,421 contacts →
	Indirect evidence “Iris Software has been a trusted software engineering partner to several Fortune 500 companies for over three decades.” Source: RevenueBase Database · checked Sep 20, 2026
13	Ensono	Indirect evidence	Downers Grove, IL, United StatesHQ checked Sep 20, 2026	1,001-5,000	3,247 contacts →
	Indirect evidence “Ensono is an expert technology adviser and managed service provider.” Source: RevenueBase Database · checked Sep 20, 2026
14	Visionet Systems INC	Indirect evidence	Cranbury, NJ, United StatesHQ checked Sep 20, 2026	10001+	3,119 contacts →
	Indirect evidence “Visionet is a premier digital technology solutions company built on the premise of disruptive innovation.” Source: RevenueBase Database · checked Sep 20, 2026
15	Mouri Tech	Indirect evidence	Irving, TX, United StatesHQ checked Sep 20, 2026	1,001-5,000	3,051 contacts →
	Indirect evidence “MOURI Tech - the global enterprise IT services provider, established in 2005, has been offering innovative solutions underscoring client success, with unwavering commitment.” Source: RevenueBase Database · checked Sep 20, 2026
16	AHEAD	Indirect evidence	Chicago, IL, United StatesHQ checked Sep 20, 2026	1,001-5,000	2,989 contacts →
	Indirect evidence “AHEAD accelerates strategy into execution by engineering integrated solutions across infrastructure, applications, data, and security.” Source: RevenueBase Database · checked Sep 20, 2026
17	Speridian Technologies	Indirect evidence	Albuquerque, NM, United StatesHQ checked Sep 20, 2026	1,001-5,000	2,619 contacts →
	Indirect evidence “Speridian Technologies is a global consulting and technology services firm that helps enterprises and public sector organizations modernize operations, enhance customer experience…” Source: RevenueBase Database · checked Sep 20, 2026
18	People Tech Group INC	Indirect evidence	Redmond, WA, United StatesHQ checked Sep 20, 2026	1,001-5,000	2,434 contacts →
	Indirect evidence “People Tech Group is a leading Enterprise Solutions, Digital Transformation, Data Intelligence, and Modern Operation services provider.” Source: RevenueBase Database · checked Sep 20, 2026
19	Trianz	Indirect evidence	Herndon, VA, United StatesHQ checked Sep 20, 2026	1,001-5,000	2,331 contacts →
	Indirect evidence “Trianz is a "transformation services as a software" company - helping enterprises accelerate cloud adoption and AI transformation through Concierto, our unified, AI-first platform…” Source: RevenueBase Database · checked Sep 20, 2026
20	IDC Technologies, INC	Indirect evidence	Milpitas, CA, United StatesHQ checked Sep 20, 2026	5,001-10,000	2,269 contacts →
	Indirect evidence “We are IDC Technologies - where people and digital innovation come together to create measurable impact.” Source: RevenueBase Database · checked Sep 20, 2026
21	CTG	Indirect evidence	Amherst, NY, United StatesHQ checked Sep 20, 2026	5,001-10,000	2,264 contacts →
	Indirect evidence “CTG, a Cegeka company, is at the forefront of digital transformation, offering innovative IT solutions and services that accelerate your strategy and project momentum.” Source: RevenueBase Database · checked Sep 20, 2026
22	Techwave	Indirect evidence	Houston, TX, United StatesHQ checked Sep 20, 2026	1,001-5,000	2,140 contacts →
	Indirect evidence “Techwave is a leading global IT and engineering services and solutions company revolutionizing digital transformation.” Source: RevenueBase Database · checked Sep 20, 2026
23	Thoughtfocus	Indirect evidence	Mckinney, TX, United StatesHQ checked Sep 20, 2026	1,001-5,000	2,097 contacts →
	Indirect evidence “ThoughtFocus, headquartered in the U.S.” Source: RevenueBase Database · checked Sep 20, 2026
24	Marlabs	Indirect evidence	New York, NY, United StatesHQ checked Sep 20, 2026	1,001-5,000	2,000 contacts →
	Indirect evidence “Marlabs is your trusted AI transformation partner with 30 years of experience solving modern challenges, with a proven track record of delivering complex technology solutions to…” Source: RevenueBase Database · checked Sep 20, 2026
25	Nous Infosystems	Indirect evidence	Edison, NJ, United StatesHQ checked Sep 20, 2026	1,001-5,000	1,926 contacts →
	Indirect evidence “Nous Infosystems is now.” Source: RevenueBase Database · checked Sep 20, 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: legacy system modernization companies. 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 legacy system modernization companies.
Partial evidence: Its own public description names part of legacy system modernization companies, so it works in or next to the category without describing itself that way.
Indirect evidence: The description shown does not name legacy system modernization companies. 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 5,200 legacy system modernization companies based in the United States

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Legacy system modernization companies based in the United States at a glance

As of Sep 20, 2026

30.4%Verified-email coverage

98.8Average contacts per company

11-50Median size (employees)

3.9%Largest-city concentration · New York

Sep 20, 2026Page data refreshed

Companies by employee count

1-10

1,773

11-50

1,686

51-200

1,086

201-500

330

501-1,000

146

1,001-5,000

125

5,001-10,000

10001+

Email recency for this list is measured worldwide rather than for United States, so it is reported there. Company counts and contact totals on this page are exact for United States, over 5,200 companies.

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 legacy system modernization companies, 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.
What qualifies: Companies headquartered in the United States whose own description of what they do matches “legacy system modernization companies”. 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 legacy system modernization companies), 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 legacy system modernization companies, and records with no verified work email. Companies headquartered outside United States are excluded even when they keep an office there.
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, 156,060 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 20, 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.

Legacy system modernization companies by metro

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 legacy system modernization companies, 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 legacy system modernization companies are there based in the United States?

RevenueBase identified 5,200 legacy system modernization companies headquartered in the United States 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?

DXC Technology, headquartered in Ashburn, tops this list with the largest team on record.

Which city has the most legacy system modernization companies?

New York leads with 203 headquartered companies, followed by Austin (148) and Houston (131).

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 156,060 verified decision-maker contacts tracked across these 5,200 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 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 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.