Modernizing businesses through AI, data, and innovative software solutions.
Top Rated15+ YearsMid-Size
Product Engineering (SaaS)AI/ML DevelopmentTop 10 Elite
The very best agencies • View detailed Top 10
Agencies 11–25
Strong contenders and rising stars
Massive IT services provider with 3,000+ professionals and 93% client return rate delivering end-to-end AI with PhD-level data scientists.
Top Rated15+ YearsEnterprise
AI/ML DevelopmentWeb Development
Global consulting firm providing enterprise data, analytics, AI, and advanced analytics strategies with modern data foundations.
Top Rated15+ YearsEnterprise
Data Engineering & AnalyticsApp Modernization & Legacy Migration
Full spectrum software development and IT outsourcing for healthcare, finance, and logistics with long-term partnership focus.
Top Rated15+ YearsEnterprise
Custom Software DevelopmentCloud Migration & Modernization
Leading IT solutions provider specializing in digital transformation, custom software development, and enterprise IT consulting since 1997.
Top RatedGoogle PartnerAWS Partner+3 more
AI/ML DevelopmentApp Modernization & Legacy Migration
IT services company providing legacy application migration services with 700+ certified integration architects for complex digital landscape transformation.
Top RatedGoogle PartnerAWS Partner+4 more
App Modernization & Legacy Migration
Custom software development agency providing legacy application modernization with focus on cloud-native transformation and cutting-edge technology integration.
Top Rated15+ YearsSmall Team
App Modernization & Legacy Migration
Global IT services company providing AI-powered legacy modernization services with proprietary RapidX, Amaze, and Tensai platforms for enterprise transformation.
Top Rated15+ YearsEnterprise
App Modernization & Legacy MigrationAI/ML Development
Technology consulting company specializing in legacy application modernization with expertise in AWS, Azure, and GCP cloud migrations and proprietary AI-powered Code Explorer tool.
Top RatedMicrosoft Partner15+ Years+1 more
App Modernization & Legacy MigrationCustom Software Development
IT services company providing cloud migration and platform modernization with expertise in legacy application transformation and data center transitions.
Top RatedSalesforce Partner15+ Years+1 more
App Modernization & Legacy Migration
Global IT services company providing legacy application modernization with NeoZeta AI agents and KRYPTON containerization platform for mainframe transformation.
Top Rated15+ YearsEnterprise
App Modernization & Legacy MigrationSRE Services
Global IT services company providing mainframe modernization with AWS Premier Consulting Partner status and proprietary UniKix rehosting software for up to 70% cost savings.
Top Rated15+ YearsEnterprise
App Modernization & Legacy MigrationLegacy Modernization
IT solutions provider offering cloud migration services with structured approaches for full-stack migration including applications, infrastructure, and DevOps.
Top RatedSalesforce Partner15+ Years+1 more
App Modernization & Legacy Migration
Software development company providing legacy modernization with focus on cloud migration, code refactoring, and application re-engineering for long-term partnerships.
Top Rated15+ YearsMid-Size
App Modernization & Legacy Migration
Software development company providing custom software development and enterprise app modernization with AI capabilities since 2009.
Top Rated15+ YearsLarge Team
App Modernization & Legacy MigrationComplete Top 25 App Modernization & Legacy Migration Agencies
Full numbered list of all 25 agencies
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Complete Top 25 App Modernization & Legacy Migration Agencies
Full numbered list of all 25 agencies
- 1.Accenture — New Jersey
- 2.Cognizant — New Jersey
- 3.IBM Consulting — New York
- 4.Kyndryl — New York
- 5.PwC — New York
- 6.ScienceSoft — Texas
- 7.Slalom — Washington
- 8.Cloudticity — Washington
- 9.Maxima Consulting — Massachusetts
- 10.Appinventiv — New York
- 11.Door3 — New York
- 12.Innowise — Georgia
- 13.Protiviti — Illinois
- 14.Andersen — New York
- 15.Charter Global — Georgia
- 16.The Intech Group — Florida
- 17.The Provato Group — Illinois
- 18.Hexaware — Georgia
- 19.Improving — Texas
- 20.Innova Solutions — Georgia
- 21.Mphasis — New York
- 22.NTT DATA — Texas
- 23.Presidio, Inc. — New York
- 24.SaM Solutions — South Carolina
- 25.Sparq — Georgia
Top 25 App Modernization & Legacy Migration Agencies — FAQ
Common questions about the best app modernization & legacy migration agencies.
Who is the #1 app modernization & legacy migration agency in the USA in 2026?
As of 2026, the top-ranked app modernization & legacy migration agency in the USA on AgencyCluster is Accenture, with an AgencyCluster Score of 100/100. Rankings are based on verified evidence across credibility, proof of work, reputation, category specialization, delivery maturity, and freshness. Rankings are updated periodically as new evidence becomes available.
How were the top 25 app modernization & legacy migration agencies in the USA selected?
This list features 25 agencies selected from AgencyCluster's curated directory. Each agency was evaluated using the AgencyCluster Score (0–100), with particular weight on demonstrated expertise in app modernization & legacy migration. Only agencies with verified credentials are eligible, and rankings cannot be purchased. The agencies on this list average 30+ years of experience. For full methodology details, see our How We Rank page.
What should I look for when choosing a app modernization & legacy migration agency from this list?
Ask about their assessment methodology — how do they decide what to refactor vs. rebuild vs. replace? Check their experience with your legacy technology (COBOL, .NET Framework, monolithic Java, etc.). Ask about their strangler fig or incremental migration approach. For large systems, ask about their risk mitigation and rollback strategy.
How much do the top app modernization & legacy migration agencies typically charge?
Legacy assessment and modernization roadmap costs $20K–$60K. Application modernization projects range from $75K–$500K+ per major system. Enterprise modernization programs can span $500K–$2M+ across multiple systems.
Trusted Rankings
Every agency on this list has been reviewed by our editorial team. Rankings are based on our transparent methodology which evaluates credibility, outcomes, and reputation.
No paid rankingsVerified credentialsUpdated regularly
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