# Top 30 professional services firms in Washington

Tamtam tracks 109 professional services firms headquartered in Washington. This list ranks the 30 largest by number of employees on LinkedIn, led by FTI Consulting, Hogan Lovells and Jones Day. Their median headcount is 1,817. Half of them were founded in 1975 or later.

The professional services companies in Washington listed here are primarily large firms specializing in legal services and business consulting. Noteworthy examples include Hogan Lovells, a global legal team providing innovative solutions, and FTI Consulting, an expert firm offering crisis management and strategic solutions. Other significant companies are Jones Day, providing comprehensive legal services worldwide, and Chemonics International, an international development company with specialists in various sectors.

A recurring pattern among these companies is their global reach, with many operating internationally. For instance, Palladium: Make It Possible collaborates with governments and communities worldwide, and BRG provides interdisciplinary consulting globally. The dominance of legal practices and business consulting firms suggests a concentration of expertise in these fields within Washington.

🇺🇸 Washington · 30 companies · Updated Nov 11, 2026

| # | Company | Industry | Headquarters | Employees | Founded |
|---|---|---|---|---|---|
| 1 | [FTI Consulting](https://www.tamtam.ai/c/fti-consulting) (fticonsulting.com)<br>Global expert firm providing crisis management, transformation consulting, and strategic solutions to organizations facing complex business challenges worldwide. | Business Consulting and Services | 🇺🇸 Washington | 10,452 | 1982 |
| 2 | [Hogan Lovells](https://www.tamtam.ai/c/hogan-lovells) (hoganlovells.com)<br>Global team of 2,600+ lawyers providing innovative legal solutions for major industries worldwide, with a focus on diversity, community impact, and business strategy alignment | Law Practice | 🇺🇸 Washington | 7,724 | 1899 |
| 3 | [Jones Day](https://www.tamtam.ai/c/jones-day) (jonesday.com)<br>Provides comprehensive legal services worldwide through a large network of lawyers collaborating across multiple disciplines and jurisdictions. | Law Practice | 🇺🇸 Washington | 6,417 | 1893 |
| 4 | [Chemonics International](https://www.tamtam.ai/c/chemonics-international) (chemonics.com)<br>An international development company with 4,000 specialists globally, focusing on various sectors like agriculture, governance, health, and supply chain solutions | Professional Services | 🇺🇸 Washington | 3,985 | 1975 |
| 5 | [Consilio LLC](https://www.tamtam.ai/c/consilio-llc) (consilio.com)<br>Offers eDiscovery, document review, flexible legal talent, legal advisory, and transformation consulting services to law firms and corporations globally. | Law Practice | 🇺🇸 Washington | 3,639 |  |
| 6 | [Palladium: Make It Possible](https://www.tamtam.ai/c/palladium-make-it-possible) (thepalladiumgroup.com)<br>Collaborates with governments, businesses, and communities to design and implement large-scale programs tackling climate, conflict, and inequality worldwide. | Business Consulting and Services | 🇺🇸 Washington | 2,845 | 1965 |
| 7 | [Covington & Burling LLP](https://www.tamtam.ai/c/covington-and-burling-llp) (cov.com)<br>Global law firm providing expert legal services with commitment to clients, teamwork, diversity, public service, and complex business challenges. | Law Practice | 🇺🇸 Washington | 2,797 | 1919 |
| 8 | [Arnold & Porter](https://www.tamtam.ai/c/arnold-and-porter) (arnoldporter.com)<br>A global law firm offering comprehensive legal services in regulatory, litigation, and transactional matters across various industries with a multidisciplinary approach | Law Practice | 🇺🇸 Washington | 2,470 |  |
| 9 | [BRG](https://www.tamtam.ai/c/brg) (thinkbrg.com)<br>Provides interdisciplinary consulting combining academic knowledge and business expertise in economics, disputes, corporate finance, and performance improvement globally. | Business Consulting and Services | 🇺🇸 Washington | 2,395 | 2010 |
| 10 | [WilmerHale](https://www.tamtam.ai/c/wilmerhale) (wilmerhale.com)<br>A leading international law firm with over 1,000 lawyers in 13 offices worldwide, specializing in government, technology, and business law Promotes diversity and public service | Law Practice | 🇺🇸 Washington | 2,356 |  |
| 11 | [Gallup](https://www.tamtam.ai/c/gallup) (gallup.com)<br>Provides analytics and advice to help leaders solve problems using over 85 years of experience and global insights on attitudes and behaviors | Business Consulting and Services | 🇺🇸 Washington | 2,320 | 1935 |
| 12 | [BakerHostetler](https://www.tamtam.ai/c/bakerhostetler) (bakerlaw.com)<br>A leading law firm with top client service and legal expertise, offering assistance with complex business and regulatory issues worldwide | Law Practice | 🇺🇸 Washington | 2,291 | 1916 |
| 13 | [EAB](https://www.tamtam.ai/c/eab) (eab.com)<br>This company partners with educational institutions to drive transformative change through data-driven insights and capabilities in enrollment, student success, strategy, analytics, and DE&I | Education | 🇺🇸 Washington | 2,131 |  |
| 14 | [Venable LLP](https://www.tamtam.ai/c/venable-llp) (venable.com)<br>A global law firm with over 900 professionals offering legal services in regulatory compliance, government affairs, corporate transactions, IP, and complex litigation to empower clients | Law Practice | 🇺🇸 Washington | 1,914 | 1900 |
| 15 | [APCO](https://www.tamtam.ai/c/apco) (apcoworldwide.com)<br>Global advisory and advocacy firm assisting organizations in building common ground to facilitate progress and achieve strategic goals effectively. | Business Consulting and Services | 🇺🇸 Washington | 1,817 | 1984 |
| 16 | [Crowell & Moring](https://www.tamtam.ai/c/crowell-and-moring) (crowell.com)<br>International law firm providing legal services across multiple continents, specializing in litigation, arbitration, regulatory, corporate, and transactional issues Committed to pro bono work and diversity | Law Practice | 🇺🇸 Washington | 1,715 | 1979 |
| 17 | [Versar Global Solutions](https://www.tamtam.ai/c/versar-global-solutions) (versar.com)<br>A Washington, DC-based company provides full lifecycle solutions for government and commercial Customers in natural, built, and digital environments worldwide | Defense and Space Manufacturing | 🇺🇸 Washington | 1,603 | 1969 |
| 18 | [Page](https://www.tamtam.ai/c/page-washington) (pagethink.com)<br>Multidisciplinary design, architecture, and engineering firm with 1,300+ staff and international offices Specializing in complex projects across various sectors Visit wwwpagethinkcom for more information | Architecture and Planning | 🇺🇸 Washington | 1,448 |  |
| 19 | [InfoCepts](https://www.tamtam.ai/c/infocepts) (infocepts.ai)<br>Infocepts specializes in using data, AI, and user-friendly analytics to help clients overcome challenges and make better business decisions | Business Consulting and Services | 🇺🇸 Washington | 1,428 | 2004 |
| 20 | [Hunton Andrews Kurth LLP](https://www.tamtam.ai/c/hunton-andrews-kurth-llp) (hunton.com)<br>A global law firm with 900+ lawyers offering comprehensive legal services in transactional, litigation, and regulatory matters across various industries and practice areas | Law Practice | 🇺🇸 Washington | 1,393 | 1901 |
| 21 | [Steptoe LLP](https://www.tamtam.ai/c/steptoe-llp) (steptoe.com)<br>Provides international legal representation, litigation advocacy, arbitration, and practical business transaction advice with over 500 professionals worldwide. | Law Practice | 🇺🇸 Washington | 1,250 | 1913 |
| 22 | [IRS, Office of Chief Counsel](https://www.tamtam.ai/c/irs-office-of-chief-counsel) (jobs.irs.gov)<br>A large tax firm with over 1,700 attorneys serving the IRS and the American public, promoting diversity, inclusion, and a balanced work environment | Law Practice | 🇺🇸 Washington | 1,114 |  |
| 23 | [ArentFox Schiff](https://www.tamtam.ai/c/arentfox-schiff) (afslaw.com)<br>Industry insiders offering practical business strategies and legal solutions to help clients reach their goals and anticipate future challenges | Law Practice | 🇺🇸 Washington | 1,004 |  |
| 24 | [Finnegan, Henderson, Farabow, Garrett & Dunner, LLP](https://www.tamtam.ai/c/finnegan-henderson-farabow-garrett-and-dunner-llp) (finnegan.com)<br>Provides comprehensive intellectual property legal services including litigation, patent strategy, and brand management with global presence and expertise. | Law Practice | 🇺🇸 Washington | 955 |  |
| 25 | [ENGIE Impact](https://www.tamtam.ai/c/engie-impact) (engieimpact.com)<br>Sustainability solutions provider for corporations, cities, and governments worldwide, offering strategic and technical support to tackle complex sustainability challenges Leader in zero-carbon transition | Environmental Services | 🇺🇸 Washington | 934 | 1996 |
| 26 | [Gallagher & Mohan](https://www.tamtam.ai/c/gallagher-and-mohan) (gallaghermohan.com)<br>Commercial real estate services firm specializing in globalizing operations, managing systems, and reducing back-office support costs for real estate companies worldwide | Outsourcing and Offshoring Consulting | 🇺🇸 Washington | 903 |  |
| 27 | [LBS](https://www.tamtam.ai/c/lbs) (versar.com)<br>Versar Global Solutions provides comprehensive lifecycle solutions for government and commercial clients in natural, built, and digital environments worldwide | Defense and Space Manufacturing | 🇺🇸 Washington | 802 | 2012 |
| 28 | [CIBT](https://www.tamtam.ai/c/cibt) (corporate.cibt.com)<br>Global provider of immigration and visa services for corporations and individuals with a team of experts in over 60 offices worldwide | Consumer Services | 🇺🇸 Washington | 785 | 1989 |
| 29 | [Compass Lexecon](https://www.tamtam.ai/c/compass-lexecon) (compasslexecon.com)<br>Provides economic consulting services to law firms, corporations, and governments, offering analysis for litigation, regulation, and strategic decisions. | Business Consulting and Services | 🇺🇸 Washington | 779 |  |
| 30 | [Nava](https://www.tamtam.ai/c/nava) (navapbc.com)<br>Nava is a consultancy and public benefit corporation dedicated to simplifying and improving government services through civic technology and inclusive design | Software Development | 🇺🇸 Washington | 729 | 2015 |

## 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 11, 2026.

## More company lists in Washington

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- [Multinational companies in Washington](https://www.tamtam.ai/l/multinational-companies-washington) (218)
- [Non-profit Organizations companies in Washington](https://www.tamtam.ai/l/non-profit-organizations-companies-washington) (145)
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## The same list elsewhere in United States

- [Professional services firms in the United States](https://www.tamtam.ai/l/professional-services-firms-united-states) (7,078)
- [Professional services firms in New York State](https://www.tamtam.ai/l/professional-services-firms-new-york-state) (955)
- [Professional services firms in California](https://www.tamtam.ai/l/professional-services-firms-california) (880)
- [Professional services firms in Texas](https://www.tamtam.ai/l/professional-services-firms-texas) (629)
- [Professional services firms in Florida](https://www.tamtam.ai/l/professional-services-firms-florida) (375)
- [Professional services firms in Virginia](https://www.tamtam.ai/l/professional-services-firms-virginia) (344)
- [Professional services firms in Illinois](https://www.tamtam.ai/l/professional-services-firms-illinois) (339)
- [Professional services firms in Massachusetts](https://www.tamtam.ai/l/professional-services-firms-massachusetts) (249)
- [Professional services firms in New Jersey](https://www.tamtam.ai/l/professional-services-firms-new-jersey) (249)
- [Professional services firms in Georgia](https://www.tamtam.ai/l/professional-services-firms-georgia) (246)
- [Professional services firms in Pennsylvania](https://www.tamtam.ai/l/professional-services-firms-pennsylvania) (245)
- [Professional services firms in Ohio](https://www.tamtam.ai/l/professional-services-firms-ohio) (195)
- [Professional services firms in Maryland](https://www.tamtam.ai/l/professional-services-firms-maryland) (176)
- [Professional services firms in Michigan](https://www.tamtam.ai/l/professional-services-firms-michigan) (172)
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- [Professional services firms in Alabama](https://www.tamtam.ai/l/professional-services-firms-alabama) (135)
- [Professional services firms in Minnesota](https://www.tamtam.ai/l/professional-services-firms-minnesota) (125)
- [Professional services firms in New York](https://www.tamtam.ai/l/professional-services-firms-new-york) (735)
- [Professional services firms in Chicago](https://www.tamtam.ai/l/professional-services-firms-chicago) (196)
- [Professional services firms in Houston](https://www.tamtam.ai/l/professional-services-firms-houston) (156)
- [Professional services firms in Atlanta](https://www.tamtam.ai/l/professional-services-firms-atlanta) (143)
- [Professional services firms in San Francisco](https://www.tamtam.ai/l/professional-services-firms-san-francisco) (130)
- [Professional services firms in Los Angeles](https://www.tamtam.ai/l/professional-services-firms-los-angeles) (108)

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Source: https://www.tamtam.ai/l/professional-services-firms-washington