Fortune 500 IT services company providing enterprise-scale cloud migration and modernization services across hybrid and multi-cloud environments.
Top RatedGoogle PartnerAWS Partner+3 more
Cloud Migration & ModernizationCybersecurity ServicesTop 10 Elite
The very best agencies • View detailed Top 10
Agencies 11–25
Strong contenders and rising stars
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
Global IT and business consulting company offering comprehensive application modernization including mainframe migration and portfolio rationalization.
Top RatedGoogle PartnerAWS Partner+4 more
Legacy Modernization
Global IT services company accelerating legacy modernization with RapidX GenAI platform for automated code refactoring and knowledge transfer.
Top RatedGoogle PartnerAWS Partner+4 more
Legacy Modernization
Digital engineering company transforming legacy environments into agile digital ecosystems through platform unification and cloud-first architecture.
Top RatedGoogle PartnerAWS Partner+4 more
Legacy ModernizationAI/ML Development
Global digital development company with 1,500+ professionals delivering custom software, AI, cloud, and cybersecurity solutions.
Top RatedGoogle PartnerAWS Partner+4 more
Custom Software DevelopmentProduct Engineering (SaaS)
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
Application modernization consulting company helping enterprises update legacy systems with cloud-native approaches and microservices architecture.
Top Rated15+ YearsSmall Team
Legacy ModernizationCustom Software Development
Boston-based MVP development company delivering investor-ready products with HIPAA compliance expertise.
Top RatedGoogle PartnerAWS Partner+4 more
MVP DevelopmentLegacy 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 modernization with 400+ applications modernized across healthcare, financial services, and logistics sectors.
Top RatedGoogle PartnerAWS Partner+2 more
Legacy ModernizationCustom Software Development
Full-cycle software development company offering AI-enhanced legacy application modernization with 30% time savings through AI Solution Accelerator.
Top Rated5+ YearsMid-Size
Legacy ModernizationCustom Software Development
Modernizing businesses through AI, data, and innovative software solutions.
Top Rated15+ YearsMid-Size
Product Engineering (SaaS)AI/ML Development
Custom app development company with extensive experience in legacy application modernization and enterprise technology platform transformation.
Top Rated15+ YearsBoutique
Legacy Modernization
IT consulting firm specializing in legacy system modernization with expertise in code refactoring, containerization, cloud migration, and process automation for enterprise clients.
Top Rated15+ YearsMid-Size
App Modernization & Legacy MigrationLegacy ModernizationComplete Top 25 Legacy Modernization Agencies
Full numbered list of all 25 agencies
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Complete Top 25 Legacy Modernization Agencies
Full numbered list of all 25 agencies
- 1.Accenture — New Jersey
- 2.Capgemini — New York
- 3.Cognizant — New Jersey
- 4.Deloitte — New York
- 5.IBM Consulting — New York
- 6.Infosys — Texas
- 7.Astadia — Arizona
- 8.HCLTech — North Carolina
- 9.Luxoft — New York
- 10.Wipro — New Jersey
- 11.DXC Technology — Virginia
- 12.NTT DATA — Texas
- 13.CGI — California
- 14.Hexaware Technologies — New Jersey
- 15.Persistent Systems — California
- 16.10Pearls — Virginia
- 17.Andersen — New York
- 18.Assembly — Florida
- 19.Cabot Technology Solutions — Massachusetts
- 20.Charter Global — Georgia
- 21.Damco Solutions — New Jersey
- 22.Devox Software — Florida
- 23.Door3 — New York
- 24.Entrance Consulting — Texas
- 25.Maxima Consulting — Massachusetts
Top 25 Legacy Modernization Agencies — FAQ
Common questions about the best legacy modernization agencies.
Who is the #1 legacy modernization agency in the USA in 2026?
As of 2026, the top-ranked legacy modernization 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 legacy modernization 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 legacy modernization. Only agencies with verified credentials are eligible, and rankings cannot be purchased. The agencies on this list average 35+ years of experience. For full methodology details, see our How We Rank page.
What should I look for when choosing a legacy modernization agency from this list?
Ask for case studies with measurable outcomes relevant to your specific project. Check team composition — do they have specialists or generalists? Ask about their communication cadence and project management approach. Request client references from companies of similar size and complexity to yours.
How much do the top legacy modernization agencies typically charge?
Project costs vary significantly based on complexity, team size, and engagement model. Request proposals from 3–5 agencies to benchmark pricing. Be cautious of quotes that are dramatically lower than others — they usually indicate corners being cut.
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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