Company lists · Data refreshed September 2026

Top 25 Legacy system modernization consultancies based in France

Name: Legacy system modernization consultancies based in France
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 28, 2026 483 companies tracked

RevenueBase identified 483 legacy system modernization consultancies headquartered in France as of September 2026 and tracks 5,761 professional contacts across them, including 1,997 with verified work emails. Paris is the largest hub.

This list covers legacy system modernization consultancies headquartered in France, 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 28, 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 28, 2026 86% judged on-target in blind review

483Companies

5,761Contacts tracked

1,997Verified emails

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The 25 largest legacy system modernization consultancies based in France

Ranked by team size

Top 25 of 483 legacy system modernization consultancies based in France, ranked by team size, largest first. Data refreshed Sep 28, 2026. RevenueBase Smart Search rates how each company's information relates to legacy system modernization consultancies: 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	Infotel	Indirect evidence	Neuilly-sur-seine, FranceHQ checked Sep 28, 2026	1,001-5,000	1,735 contacts →
	Indirect evidence “Infotel accompagne les directions Informatiques et Métiers des grandes entreprises depuis 45 ans (Airbus, Air France, PSA, BNP Paribas, Banque de France ou encore BPCE, etc.).” Source: RevenueBase Database · checked Sep 28, 2026
2	Adservio	Indirect evidence	Puteaux, FranceHQ checked Sep 28, 2026	201-500	161 contacts →
	Indirect evidence “We build a resilient digital experience.” Source: RevenueBase Database · checked Sep 28, 2026
3	RBI	Indirect evidence	Rennes, FranceHQ checked Sep 28, 2026	11-50	133 contacts →
	Indirect evidence “Dans un monde où tout s’accélère, la transformation numérique n’est plus une option : c’est un levier de compétitivité.” Source: RevenueBase Database · checked Sep 28, 2026
4	IS Technologies	Indirect evidence	Courbevoie Cedex, FranceHQ checked Sep 28, 2026	n/a	127 contacts →
	Indirect evidence “IS Technologies est une société de conseils et de services en informatique basée à La Défense.” Source: RevenueBase Database · checked Sep 28, 2026
5	ENGIT	Indirect evidence	Valbonne, FranceHQ checked Sep 28, 2026	51-200	102 contacts →
	Indirect evidence “engIT \| Innovation IT & Transformation digitale - Faire du conseil différemment Depuis 2017, engIT accompagne les entreprises dans leurs projets stratégiques d'innovation…” Source: RevenueBase Database · checked Sep 28, 2026
6	Novahé	Partial evidence	Saint Cloud Cedex, FranceHQ checked Sep 28, 2026	51-200	92 contacts →
	Partial evidence “En 2018, AS-PC, EVEA TECHNOLOGY et INETD CONSULTING deviennent NOVAHE < Novahé accompagne les ETIs et les Grands Comptes dans l’optimisation et l’urbanisation de leur Système…” Source: RevenueBase Database · checked Sep 28, 2026
7	Isitix	Indirect evidence	FranceHQ checked Sep 28, 2026	n/a	83 contacts →
	Indirect evidence “Depuis 20 ans, Isitix accompagne vos projets informatiques et numériques.” Source: RevenueBase Database · checked Sep 28, 2026
8	Tlti Ingénierie Numérique	Indirect evidence	Paris, FranceHQ checked Sep 28, 2026	11-50	69 contacts →
	Indirect evidence “CONSEIL : Un savoir-faire reconnu et structuré autour d'axes métiers.” Source: RevenueBase Database · checked Sep 28, 2026
9	Artik Consulting	Indirect evidence	Issy-les-moulineaux, FranceHQ checked Sep 28, 2026	11-50	59 contacts →
	Indirect evidence “Artik Consulting Artik est une société de conseil technologique qui accompagne les grandes entreprises dans leurs projets de transformation SI.” Source: RevenueBase Database · checked Sep 28, 2026
10	Kern Consulting	Partial evidence	Paris, FranceHQ checked Sep 28, 2026	51-200	59 contacts →
	Partial evidence “Kern Consulting est un cabinet d'experts spécialistes de la transformation de l'entreprise, convaincus que le Système d'Information en est un levier incontournable.” Source: RevenueBase Database · checked Sep 28, 2026
11	Diggers	Indirect evidence	Paris, FranceHQ checked Sep 28, 2026	51-200	58 contacts →
	Indirect evidence “Diggers est un cabinet de conseil facilitateur de projets et de transformations, spécialisé dans les métiers de l'IT (développement, data & IA, devops, cloud) et une agence de…” Source: RevenueBase Database · checked Sep 28, 2026
12	Syspertec Group	Partial evidence	Saint-cloud, FranceHQ checked Sep 28, 2026	11-50	53 contacts →
	Partial evidence “Since 1993, Syspertec Group has been developing software solutions designed to simplify information system integration and modernize complex technical environments.” Source: RevenueBase Database · checked Sep 28, 2026
13	Lenstra	Indirect evidence	Paris, FranceHQ checked Sep 28, 2026	51-200	53 contacts →
	Indirect evidence “Lenstra is a consultancy that specialises in Tech.” Source: RevenueBase Database · checked Sep 28, 2026
14	Onefirst	Partial evidence	Puteaux, FranceHQ checked Sep 28, 2026	51-200	49 contacts →
	Partial evidence “Onefirst Group is a Consultancy specialising in Information Systems Management and Digital Transformation.” Source: RevenueBase Database · checked Sep 28, 2026
15	Spikeelabs	Partial evidence	Rennes, FranceHQ checked Sep 28, 2026	51-200	45 contacts →
	Partial evidence “SpikeeLabs travaille auprès de ses clients sur la conception et la réalisation de leur système d’information.” Source: RevenueBase Database · checked Sep 28, 2026
16	Ootary	Partial evidence	Soultz-haut-rhin, FranceHQ checked Sep 28, 2026	11-50	45 contacts →
	Partial evidence “Simplify your IT projects and accelerate your digital transformation Whether it’s migrating to an ERP system, optimizing your IT infrastructure, or managing data flows… these are…” Source: RevenueBase Database · checked Sep 28, 2026
17	Ness Technologies	Indirect evidence	Saint Michel Sur Orge, FranceHQ checked Sep 28, 2026	51-200	45 contacts →
	Indirect evidence Source: RevenueBase Database · checked Sep 28, 2026
18	Kertios	Indirect evidence	Suresnes, FranceHQ checked Sep 28, 2026	11-50	43 contacts →
	Indirect evidence “Le groupe Kertios est composé d'activités de Conseil et de Technologies.” Source: RevenueBase Database · checked Sep 28, 2026
19	Asenium Consulting	Indirect evidence	La Défense, FranceHQ checked Sep 28, 2026	51-200	41 contacts →
	Indirect evidence “Asenium, a key player in digital and IT transformation consulting, has been providing highly qualified consultants since 2005.” Source: RevenueBase Database · checked Sep 28, 2026
20	Adonis Groupe	Indirect evidence	Paris, FranceHQ checked Sep 28, 2026	51-200	37 contacts →
	Indirect evidence “Suivez la page entreprise ADONIS et restez informés de notre actualité Profil : QUI SOMMES-NOUS?” Source: RevenueBase Database · checked Sep 28, 2026
21	Move Solutions	Strong evidence	69002, FranceHQ checked Sep 28, 2026	51-200	35 contacts →
	Strong evidence “Move Solutions is an IT services company specialized in development and transformation of information systems : Data Migration, Modernization and Maintenance.” Source: RevenueBase Database · checked Sep 28, 2026
22	Management Square	Indirect evidence	Montigny-le-bretonneux, FranceHQ checked Sep 28, 2026	51-200	34 contacts →
	Indirect evidence “Depuis sa création, Management Square s'est positionné comme un acteur de référence dans l'accompagnement des entreprises face aux défis actuels du monde numérique.” Source: RevenueBase Database · checked Sep 28, 2026
23	Kp2i	Partial evidence	Paris, FranceHQ checked Sep 28, 2026	51-200	33 contacts →
	Partial evidence “KP2i est un cabinet de Conseil & de Services qui vous accompagne pour transformer votre système d’information en un véritable partenaire business.” Source: RevenueBase Database · checked Sep 28, 2026
24	Nexen Partners	Indirect evidence	Issy-les-moulineaux, FranceHQ checked Sep 28, 2026	11-50	32 contacts →
	Indirect evidence “Nexen is an IS consulting agency funded in 2018 by several experienced consultants, who share the belief that ensuring customer satisfaction as much as employees’ growth is the…” Source: RevenueBase Database · checked Sep 28, 2026
25	Gaia Mini Systemes	Indirect evidence	Lyon, FranceHQ checked Sep 28, 2026	11-50	31 contacts →
	Indirect evidence “Nous sommes des experts en #IBMi depuis plus de 30 ans.” Source: RevenueBase Database · checked Sep 28, 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 consultancies. 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 consultancies.
Partial evidence: Its own public description names part of legacy system modernization consultancies, 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 consultancies. 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 483 legacy system modernization consultancies based in France

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Legacy system modernization consultancies based in France at a glance

As of Sep 28, 2026

34.7%Verified-email coverage

11.9Average contacts per company

1-10Median size (employees)

24.2%Largest-city concentration · Paris

Sep 28, 2026Page data refreshed

Companies by employee count

1-10

334

11-50

101

51-200

201-500

501-1,000

1,001-5,000

Email recency for this list is measured worldwide rather than for France, so it is reported there. Company counts and contact totals on this page are exact for France, over 483 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 consultancies, 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 France whose own description of what they do matches “legacy system modernization consultancies”. 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 consultancies), 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 consultancies, and records with no verified work email. Companies headquartered outside France 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, 1,997 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 28, 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 consultancies by metro

Legacy system modernization consultancies in Paris117

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 consultancies, 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 consultancies are there based in France?

RevenueBase identified 483 legacy system modernization consultancies headquartered in France 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?

Infotel, headquartered in Neuilly-Sur-Seine, tops this list with the largest team on record.

Which city has the most legacy system modernization consultancies?

Paris leads with 117 headquartered companies, followed by Lyon (20) and Toulouse (12).

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 1,997 verified decision-maker contacts tracked across these 483 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 28, 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.