Company lists · Data refreshed September 2026
Top 25 Legacy dot net modernization firms based in the United States
RevenueBase identified 91 legacy dot net modernization firms headquartered in the United States as of September 2026 and tracks 1,366 professional contacts across them, including 467 with verified work emails. Austin is the largest hub.
This list covers legacy dot net modernization firms 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.
The 25 largest legacy dot net modernization firms based in the United States
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 206 contacts → | ||||
Partial evidence “Astadia is the industry leader for mainframe migrations and modernizations.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 2 | 108 contacts → | ||||
Partial evidence “Founded in 2001, EvolveWare provides seamless application modernization journeys for enterprises, government organizations and global partners.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 3 | 96 contacts → | ||||
Indirect evidence “Callibrity is the software consultancy helping clients do more with technology.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 4 | 86 contacts → | ||||
Indirect evidence “AQL Technologies is a Microsoft Solutions Partner in Digital App & Innovation and Data & AI providing the highest level of IT expertise and customer satisfaction for the past 15…” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 5 | 86 contacts → | ||||
Partial evidence “Maintain, modernize, and understand your.NET, PHP, & C++ codebase.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 6 | 77 contacts → | ||||
Partial evidence “Softacom is a full-cycle business app migration and modernization provider.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 7 | 73 contacts → | ||||
Indirect evidence “Ispirer Systems is an international software company that provides the customers with the effective way to improve IT infrastructure.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 8 | 56 contacts → | ||||
Strong evidence “The CloudFrame Modernization Suite is the most advanced legacy modernization software in the industry.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 9 | 52 contacts → | ||||
Partial evidence “As a leading provider of software modernization services, TSRI enables technology readiness for the Cloud and other modern architecture environments.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 10 | 51 contacts → | ||||
Partial evidence “Modern Systems empowers efficiency, agility, and competitive advantage through core application modernization.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 11 | 50 contacts → | ||||
Indirect evidence “We are guided by a singular mission: to be the dependable ally our clients rely on, empowering them to amplify their competitive edge by implementing cutting-edge software…” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 12 | 37 contacts → | ||||
Partial evidence “Updraft is a Chicago-based company providing automated software modernization tools to companies and systems integrators (SIs) needing exceptionally high quality code when…” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 13 | 34 contacts → | ||||
Partial evidence “Clear Measure is a full-service software architecture and engineering firm focused on mission-critical applications built on Microsoft.NET and Azure.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 14 | 20 contacts → | ||||
Indirect evidence “At Eradani, we understand the wisdom of the ancient saying that you cannot know where you are going if you do not understand where you have been.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 15 | 15 contacts → | ||||
Indirect evidence “Mertech is a leading provider of application development solutions.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 16 | 13 contacts → | ||||
Partial evidence “From modernizing legacy systems to implementing cutting-edge platforms, we deliver scalable, reliable, and future-ready solutions that empower businesses to move forward with…” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 17 | 12 contacts → | ||||
Strong evidence “At AveriSource, our mission is to help you achieve your legacy modernization objectives.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 18 | 9 contacts → | ||||
Indirect evidence “Keypress Software Development Group builds custom mission-critical business software and industry-focused SaaS solutions that help organizations streamline operations, modernize…” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 19 | 9 contacts → | ||||
Indirect evidence “MARTEX Software, Inc.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 20 | 8 contacts → | ||||
Indirect evidence “We founded Sovereign Systems, LLC in 2016 based on the core values of integrity, hard work, and serving the client's best interest.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 21 | 8 contacts → | ||||
Partial evidence “Prime TSR is a technology modernization consultancy.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 22 | 8 contacts → | ||||
Partial evidence “Software Development, Application Development, App Development, Application Migration, Cloud Migration, App Modernization, Database Migration Solutions Architecting, Project…” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 23 | 8 contacts → | ||||
Indirect evidence “QX Software Services (QXSS) is a part of the QX group of companies with employees.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 24 | 7 contacts → | ||||
Partial evidence “YTG is a Veteran-Owned, U.S-based technology consultancy that helps companies modernize legacy systems, migrate to the cloud, and implement AI solutions in Azure.” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
| 25 | 7 contacts → | ||||
Strong evidence “Unlocking Legacy Code with AI, Automated, Accurate, Future-Ready Updraft, powered by Natsoft, is an AI-driven legacy modernization platform that transforms complex, undocumented…” Source: RevenueBase Database · checked Sep 20, 2026Thanks. The Data Team will review it. | |||||
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 dot net modernization firms. 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 dot net modernization firms.
- Partial evidence
- Its own public description names part of legacy dot net modernization firms, so it works in or next to the category without describing itself that way.
- Indirect evidence
- The description shown does not name legacy dot net modernization firms. 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 91 legacy dot net modernization firms based in the United States
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Legacy dot net modernization firms based in the United States at a glance
As of Sep 20, 2026Companies by employee count
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 91 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 dot net modernization firms, 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 dot net modernization firms”. 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 dot net modernization firms), 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 dot net modernization firms, 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, 467 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.
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 dot net modernization firms, 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 dot net modernization firms are there based in the United States?
RevenueBase identified 91 legacy dot net modernization firms 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?
Astadia, headquartered in St Louis, tops this list with the largest team on record.
Which city has the most legacy dot net modernization firms?
Austin leads with 3 headquartered companies, followed by Dallas (3) and Houston (3).
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 467 verified decision-maker contacts tracked across these 91 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.
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