Company lists · Data refreshed September 2026

Top 25 Labor union consulting firms based in the United States

Name: Labor union consulting firms based in the United States
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Sep 28, 2026 471 companies tracked

RevenueBase identified 471 labor union consulting firms headquartered in the United States as of September 2026 and tracks 8,678 professional contacts across them, including 5,178 with verified work emails. New York is the largest hub.

This list covers labor union consulting 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 28, 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.

How to read this list HQ checked on every row RevenueBase Smart Search rating on every row Refreshed Sep 28, 2026 86% judged on-target in blind review

471Companies

8,678Contacts tracked

5,178Verified emails

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The 25 largest labor union consulting firms based in the United States

Ranked by team size

Top 25 of 471 labor union consulting firms based in the United States, ranked by team size, largest first. Data refreshed Sep 28, 2026. RevenueBase Smart Search rates how each company's information relates to labor union consulting firms: strong evidence (its own description names it), partial (names part of it), indirect (matched on the rest of its profile rather than the description shown). Click a contact count to view that company's people.
#	Company	RevenueBase Smart Search	Headquarters	Employees	Contacts
1	Littler	Partial evidence	San Francisco, CA, United StatesHQ checked Sep 28, 2026	1,001-5,000	2,555 contacts →
	Partial evidence “Littler is the largest global employment and labor law practice, representing management in all aspects of employment and labor law and serving as a single-source solution…” Source: RevenueBase Database · checked Sep 28, 2026
2	Jackson Lewis P.C	Partial evidence	New York, United StatesHQ checked Sep 28, 2026	1,001-5,000	2,285 contacts →
	Partial evidence “Focused on employment and labor law since 1958, Jackson Lewis P.C.’s attorneys located in major cities nationwide consistently identify and respond to new ways workplace law…” Source: RevenueBase Database · checked Sep 28, 2026
3	Constangy	Indirect evidence	Atlanta, GA, United StatesHQ checked Sep 28, 2026	201-500	429 contacts →
	Indirect evidence “Constangy, Brooks, Smith & Prophete has more than 250 attorneys across 21 states and the District of Columbia, offering services including the defense of single and…” Source: RevenueBase Database · checked Sep 28, 2026
4	Outten & Golden LLP	Indirect evidence	New York, NY, United StatesHQ checked Sep 28, 2026	51-200	150 contacts →
	Indirect evidence “Outten & Golden is a nationally recognized law firm for employees.” Source: RevenueBase Database · checked Sep 28, 2026
5	Martenson, Hasbrouck & Simon LLP	Indirect evidence	Brookhaven, GA, United StatesHQ checked Sep 28, 2026	51-200	119 contacts →
	Indirect evidence “Martenson, Hasbrouck & Simon LLP is headquartered in Atlanta, with offices in Carlsbad, Chicago, Dallas, New York, and Sacramento, making us geographically and strategically…” Source: RevenueBase Database · checked Sep 28, 2026
6	People Results	Indirect evidence	Troy, MI, United StatesHQ checked Sep 28, 2026	51-200	87 contacts →
	Indirect evidence “People Results is an experienced team of consultants who collaborate, innovate, and anticipate mission-critical challenges and deliver impactful business results.” Source: RevenueBase Database · checked Sep 28, 2026
7	Willig, Williams & Davidson	Strong evidence	Philadelphia, PA, United StatesHQ checked Sep 28, 2026	51-200	80 contacts →
	Strong evidence “Willig, Williams & Davidson is one of the largest and most respected union-side labor law firms in the United States.” Source: RevenueBase Database · checked Sep 28, 2026
8	D. Hilton Associates, INC	Indirect evidence	The Woodlands, TX, United StatesHQ checked Sep 28, 2026	11-50	77 contacts →
	Indirect evidence “D.” Source: RevenueBase Database · checked Sep 28, 2026
9	Ballard Rosenberg Golper & Savitt	Partial evidence	Encino, CA, United StatesHQ checked Sep 28, 2026	11-50	50 contacts →
	Partial evidence “Ballard Rosenberg Golper & Savitt, LLP is an A-V rated law firm engaged exclusively in the practice of labor and employment law on behalf of employers and management.” Source: RevenueBase Database · checked Sep 28, 2026
10	Bredhoff & Kaiser Pllc	Indirect evidence	Washington, DC, United StatesHQ checked Sep 28, 2026	11-50	49 contacts →
	Indirect evidence “Bredhoff & Kaiser PLLC is one of the nation’s preeminent law firms devoted to empowering workers and the institutions that advocate for them.” Source: RevenueBase Database · checked Sep 28, 2026
11	Union ONE	Strong evidence	Lake Barrington, IL, United StatesHQ checked Sep 28, 2026	51-200	48 contacts →
	Strong evidence “Welcome to Union One, a national advisory, brokerage, and technology firm serving labor unions.” Source: RevenueBase Database · checked Sep 28, 2026
12	The Kullman Firm	Partial evidence	New Orleans, LA, United StatesHQ checked Sep 28, 2026	51-200	47 contacts →
	Partial evidence “Whether vigorously protecting your business and reputation from wrongful accusations or tackling other complex labor & employment issues nationwide, Kullman brings powerful…” Source: RevenueBase Database · checked Sep 28, 2026
13	LAW Offices Of Joseph A. Romano, P.C	Indirect evidence	Yonkers, NY, United StatesHQ checked Sep 28, 2026	51-200	44 contacts →
	Indirect evidence “The Law Offices of Joseph A.” Source: RevenueBase Database · checked Sep 28, 2026
14	Allen Norton & Blue, P.A	Partial evidence	Coral Gables, FL, United StatesHQ checked Sep 28, 2026	51-200	42 contacts →
	Partial evidence “Labor and Employment Law is all we do.” Source: RevenueBase Database · checked Sep 28, 2026
15	LRI Consulting Services, Inc. Approachable Leadership	Partial evidence	Broken Arrow, OK, United StatesHQ checked Sep 28, 2026	11-50	41 contacts →
	Partial evidence “LRI Consulting Services, Inc.” Source: RevenueBase Database · checked Sep 28, 2026
16	Lindner & Marsack, S.C	Partial evidence	Milwaukee, WI, United StatesHQ checked Sep 28, 2026	11-50	40 contacts →
	Partial evidence “Lindner & Marsack is one of the nation's pre-eminent law firms specializing in labor and employment law.” Source: RevenueBase Database · checked Sep 28, 2026
17	Clemans, Nelson & Associates, INC	Strong evidence	Columbus, OH, United StatesHQ checked Sep 28, 2026	11-50	40 contacts →
	Strong evidence “Clemans Nelson is the preeminent public sector labor relations and human resource consulting firm in the state of Ohio.” Source: RevenueBase Database · checked Sep 28, 2026
18	FH Solutions Group	Strong evidence	District Of Columbia, United StatesHQ checked Sep 28, 2026	11-50	40 contacts →
	Strong evidence “FH Solutions Group (FHSG) is a national human resources and labor relations consulting firm headquartered in Washington, DC.” Source: RevenueBase Database · checked Sep 28, 2026
19	Cohen, Weiss And Simon LLP	Partial evidence	New York, NY, United StatesHQ checked Sep 28, 2026	11-50	39 contacts →
	Partial evidence “At Cohen, Weiss and Simon LLP, we are proud of our reputation as one of the nation's leading firms devoted exclusively to the interests of labor and working people.” Source: RevenueBase Database · checked Sep 28, 2026
20	Barran Liebman LLP	Partial evidence	Portland, OR, United StatesHQ checked Sep 28, 2026	11-50	39 contacts →
	Partial evidence “At Barran Liebman LLP our experienced and dedicated attorneys focus on representing employers and finding solutions for their employment law and labor management needs.” Source: RevenueBase Database · checked Sep 28, 2026
21	O'donoghue & O'donoghue LLP	Partial evidence	Washington, DC, United StatesHQ checked Sep 28, 2026	11-50	35 contacts →
	Partial evidence “O'Donoghue & O'Donoghue LLP is one of the largest and oldest union-side law firms in the United States, with offices in Washington, D.C, Philadelphia, Pennsylvania, and Annapolis…” Source: RevenueBase Database · checked Sep 28, 2026
22	Elarbee Thompson	Partial evidence	Atlanta, GA, United StatesHQ checked Sep 28, 2026	11-50	31 contacts →
	Partial evidence “Elarbee Thompson, an award-winning Atlanta based law firm, specializes in matters of employment and labor law and complex litigation.” Source: RevenueBase Database · checked Sep 28, 2026
23	Weinberg, Roger & Rosenfeld	Strong evidence	Alameda, CA, United StatesHQ checked Sep 28, 2026	51-200	29 contacts →
	Strong evidence “A Law Firm For The People Who Keep America Working Weinberg, Roger & Rosenfeld is one of the nation’s leading firms representing unions and working people in all aspects of labor…” Source: RevenueBase Database · checked Sep 28, 2026
24	Union Insurance Group	Strong evidence	Chicago, IL, United StatesHQ checked Sep 28, 2026	11-50	28 contacts →
	Strong evidence “Union Insurance Group represents over 6,800 labor organizations including international unions, district councils, building trades councils, federations, apprenticeship programs…” Source: RevenueBase Database · checked Sep 28, 2026
25	Spear Wilderman	Partial evidence	Philadelphia, United StatesHQ checked Sep 28, 2026	11-50	28 contacts →
	Partial evidence “Law practice representing labor since 1937.” Source: RevenueBase Database · checked Sep 28, 2026

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: labor union consulting 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 labor union consulting firms.
Partial evidence: Its own public description names part of labor union consulting firms, so it works in or next to the category without describing itself that way.
Indirect evidence: The description shown does not name labor union consulting 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 471 labor union consulting firms based in the United States

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Labor union consulting firms based in the United States at a glance

As of Sep 28, 2026

59.7%Verified-email coverage

18.4Average contacts per company

1-10Median size (employees)

7.0%Largest-city concentration · New York

Sep 28, 2026Page data refreshed

Companies by employee count

1-10

301

11-50

133

51-200

201-500

1,001-5,000

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 471 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 labor union consulting 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 “labor union consulting 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 labor union consulting 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 labor union consulting 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, 5,178 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 28, 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.

Labor union consulting firms by metro

Labor union consulting firms in New York33

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 labor union consulting 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 labor union consulting firms are there based in the United States?

RevenueBase identified 471 labor union consulting 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?

Littler, headquartered in San Francisco, tops this list with the largest team on record.

Which city has the most labor union consulting firms?

New York leads with 33 headquartered companies, followed by Los Angeles (23) and Washington (21).

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 5,178 verified decision-maker contacts tracked across these 471 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 28, 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.