The consulting firms in Irvine include a mix of large established companies and younger firms, primarily focused on IT services, environmental solutions, and general business consulting. Among them, Alliant Insurance Services provides insurance brokerage and consulting, Salas O'Brien is an employee-owned engineering firm, and ADEC Innovations specializes in ESG needs and sustainability performance. Trace3 focuses on data, security, and cloud solutions.
Many of these firms, such as Caylent and Neudesic, an IBM Company, specialize in IT services and consulting, often with a focus on cloud technologies or digital modernization. A common thread across these companies is their emphasis on providing strategic guidance and technological solutions to help businesses transform and improve their operations.
| # | Company | Employees | |||
|---|---|---|---|---|---|
| 1 |
Alliant Insurance Servicesalliant.com
Provides innovative insurance brokerage and consulting services, supporting diverse clients with expert teams to help grow businesses and communities. |
6,616 | |||
| 2 |
Salas O'Briensalasobrien.com
Employee-owned engineering firm focused on advancing the human experience through the built environment Top-ranked, with a strong emphasis on impact and sustainability |
2,295 | |||
| 3 |
ADEC Innovationsadec-innovations.com
ADEC Innovations offers integrated industry expertise, data management, and software services to meet ESG needs, improve sustainability performance, and drive operational efficiencies globally |
1,801 | |||
| 4 |
Trace3trace3.com
Consulting on, integrating, and operating data, security, and cloud solutions to drive business transformation and create measurable value for clients |
1,440 | |||
| 5 |
Caylentcaylent.com
Cloud native services provider helping organizations optimize people and technology with AWS, enabling innovation and ambitious ideas to thrive |
899 | |||
| 6 |
NTrustntrustinfotech.com
Real estate lease administration solution provider offering advanced CRE software platforms and technical/back office services to international and domestic companies of all sizes |
814 | |||
| 7 |
Neudesic, an IBM Companyneudesic.com
Trusted technology partner specializing in digital modernization, custom application development, managed services, and business software products for impactful business results |
800 | |||
| 8 |
FCSfirstcarbonsolutions.com
Leading provider of environmental, sustainability, and compliance solutions with expertise in CEQA/NEPA, compliance, permitting, natural resources management, and more Join our team! |
613 | |||
| 9 |
Hitachi Solutions Americaglobal.hitachi-solutions.com
Global IT consulting firm specializing in Microsoft platform solutions, delivering sustainable business modernization and empowering customer growth worldwide. |
589 | |||
| 10 | 582 | ||||
| 11 |
Altezzasys INCaltezzasys.com
A global technology services provider offering staffing, outsourcing, consulting, and digital solutions to align technology innovation with business strategy worldwide |
571 | |||
| 12 |
Triotrioadvisory.com
Global energy and sustainability advisory helping large clients transition to a net-zero future through strategy, implementation, and advanced technological solutions |
475 | |||
| 13 |
Resources Global Professionalsrgp.com
Specializing in enterprise risk management consulting to help businesses identify, assess, and mitigate risks for improved decision-making and operational success |
459 | |||
| 14 |
Vision33vision33.com
Company provides ERP, automation, and integration solutions to help organizations grow, offering consulting and technology services to overcome business challenges and achieve goals globally |
402 | |||
| 15 |
Authority Partnersauthoritypartners.com
Global technology strategy consulting and custom software development company delivering digital transformation solutions to increase engagement, sales, productivity, and create value for clients |
390 | |||
Want more companies than this list?This page shows the largest ones only. Connect to Tamtam to see every company that matches, filter by size, industry or growth, and reach their decision-makers. | |||||
| 16 |
SMA: The Program Lifecycle Companysmawins.com
SMA helps companies enhance competitiveness through consulting, program management, and technical support, guided by values of professionalism, impact, and courage |
311 | |||
| 17 |
SETA Internationalseta-international.com
Global leader in custom software development, specializing in end-to-end technology services and solutions for over 500 clients across a variety of industries worldwide |
278 | |||
| 18 |
Interwest Consulting Groupinterwestgrp.com
Professional consulting services for public agencies in California, Nevada, and Colorado Expert team with experience in public works, engineering, and building departments, focusing on thriving communities |
233 | |||
| 19 |
XCentiumxcentium.com
Aligning technology strategy with business goals, delivering digital experiences, and modernizing platforms for long-term success through tailored solutions. |
207 | |||
| 20 |
RBF Consulting, a Company of Michael Baker Internationalrbf.com
A leading civil engineering and design firm providing a wide range of services for public, governmental, and private organizations worldwide |
205 | |||
| 21 |
eJAmericaejamerica.com
The company provides a range of digital services including application, cyber security, IT consulting, data center, cloud services, and IT staffing They also offer management consulting, ERP solutions, and outsourcing strategies |
183 | |||
| 22 |
Leighton - A Verdantas Companyverdantas.com
A company providing environmental, geotechnical, materials testing, and inspection services with a team of engineers, geologists, technicians, and inspectors Offering various job opportunities |
182 | |||
| 23 |
Approgence Technologies Incapprogence.com
IT services company offering systems integration, software solutions, staff augmentation, BI, Analytics, Data management, mobile apps, ERP integration, and executive search services |
16 | |||
| 24 |
Sovereign Powersovereignpower.com
This company partners with clients to develop enterprise strategies using exponential technologies, focusing on digital transformation, innovation, and revenue growth |
9 | |||
| 25 |
Real Estate Economicszondahome.com
A market research company providing web-based analytic tools and consulting services to the homebuilding industry for informed decision-making |
7 | |||
| 26 |
Cloudpointecloudpointe.com
A customer-centric Salesforce consultancy in Southern California helping mid-to-large companies solve business challenges with strategic planning, integration, development, and ongoing support |
6 | |||
| 27 |
Proaxive Solutions,LLCproaxive.net
The company provides IT consulting services to help clients align their business and processes with technology strategies in a digital-driven world |
6 | |||
| 28 |
Nakunj Incnakunj.com
Specializing in personalized Data Analytics and AI solutions to solve unique business problems, ensuring excellent ROI and competitive advantage for customers |
4 | |||
| 29 |
Scaleocity Worksscaleocityworks.com
This company provides full-service HR and workforce management solutions to help businesses navigate compliance, talent retention, and operational challenges for sustainable growth |
3 | |||
| 30 |
Priority Services Group Incprioritysg.com
Specializing in logistics and supply chain consulting, design, analysis, and contract management from manufacturing to distribution, with expertise in implementation and training |
2 | |||
Turn this list into pipeline
Tamtam finds the decision-makers at every company on a list like this one, with verified emails, phone numbers and the buying signals that tell you when to reach out.
How this list is built
Every company on this list has a Tamtam company profile. The industry is the one the company gives on LinkedIn; categories such as SaaS or fintech are classified by Tamtam's AI from the company's website and LinkedIn page; and the headquarters city must match the company's own address. Companies are ranked by the number of employees on LinkedIn, and the list is refreshed every night. Classifications can be wrong, so treat the list as a starting point rather than an official ranking. Last updated Nov 12, 2026.
More company lists in Irvine
- The largest companies in Irvine 548
- Multinational companies in Irvine 124
- Companies with in-house R&D in Irvine 64
- Hardware manufacturers in Irvine 63
- Manufacturers in Irvine 63
- Professional services firms in Irvine 61
- IT Services and IT Consulting companies in Irvine 52
- IT services companies in Irvine 51
- SaaS companies in Irvine 50
- Software Development companies in Irvine 42
- Financial services firms in Irvine 40
- AI companies in Irvine 37
- Retail chains in Irvine 36
- Financial Services companies in Irvine 35
- Companies with a mobile app in Irvine 32
- Real Estate companies in Irvine 29
- Subscription businesses in Irvine 27
- Franchise networks in Irvine 26
- Medical device companies in Irvine 25
The same list elsewhere in United States
- Consulting firms in the United States 4,382
- Consulting firms in California 551
- Consulting firms in New York State 474
- Consulting firms in Texas 453
- Consulting firms in Virginia 283
- Consulting firms in Illinois 238
- Consulting firms in New Jersey 215
- Consulting firms in Florida 186
- Consulting firms in Georgia 167
- Consulting firms in Massachusetts 153
- Consulting firms in Pennsylvania 144
- Consulting firms in Ohio 115
- Consulting firms in Maryland 112
- Consulting firms in Washington State 106
- Consulting firms in Michigan 103
- Consulting firms in North Carolina 85
- Consulting firms in Alabama 78
- Consulting firms in Colorado 77
- Consulting firms in New York 368
- Consulting firms in Chicago 127
- Consulting firms in Houston 99
- Consulting firms in San Francisco 88
- Consulting firms in Atlanta 84
- Consulting firms in Washington 70