Company lists · Data refreshed September 2026

Top 25 Tax law firms based in Washington, United States

RevenueBase identified 86 tax law firms headquartered in Washington, United States as of September 2026 and tracks 7,609 professional contacts across them, including 4,829 with verified work emails. New York is the largest hub.

This list covers tax law firms headquartered in Washington, 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 6, 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 6, 2026 86% judged on-target in blind review
86Companies
7,609Contacts tracked
4,829Verified emails
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The 25 largest tax law firms based in Washington, United States

Ranked by team size
Top 25 of 86 tax law firms based in Washington, United States, ranked by team size, largest first. Data refreshed Sep 6, 2026. RevenueBase Smart Search rates how each company's information relates to tax law 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.
#CompanyRevenueBase Smart SearchHeadquartersEmployeesContacts
1Indirect evidenceWashington, DC, United StatesHQ checked Sep 6, 20261,001-5,0002,333 contacts →

“Arnold & Porter combines sophisticated regulatory, litigation, and transactional capabilities to resolve clients’ most complex issues.”

Source: company website · checked Sep 6, 2026
2Partial evidenceWashington, DC, United StatesHQ checked Sep 6, 20261,001-5,0002,073 contacts →

“Recognized as one of the top firms for client service and quality of legal services, BakerHostetler is a leading law firm that helps clients around the world address their most…”

Source: company website · checked Sep 6, 2026
3Partial evidenceWashington, DC, United StatesHQ checked Sep 6, 20261,001-5,0001,790 contacts →

“Committed to Your Success – As a law firm of more than 900 professionals, Venable delivers legal services globally in every area of regulatory compliance, government affairs…”

Source: company website · checked Sep 6, 2026
4Indirect evidenceWashington, DC, United StatesHQ checked Sep 6, 2026501-1,000576 contacts →

“Founded in 1983, Wiley is a dominant presence in the nation’s capital.”

Source: company website · checked Sep 6, 2026
5Partial evidenceWashington, DC, United StatesHQ checked Sep 6, 202651-20054 contacts →

“Think, LLP is a national professional tax services firm that consists of former Big-4 partners from the national tax practices, attorneys, CPAs, engineers, former IRS technicians…”

Source: company website · checked Sep 6, 2026
6Strong evidenceWashington, DC, United StatesHQ checked Sep 6, 202611-5050 contacts →

“Ivins, Phillips & Barker is exclusively engaged in the practice of federal tax, benefits and compensation, and estate and gift tax law.”

Source: company website · checked Sep 6, 2026
7Partial evidenceWashington, DC, United StatesHQ checked Sep 6, 202611-5034 contacts →

“Kozusko Harris Vetter Wareh Duncan LLP ("KHD") is a boutique trusts and estates law firm serving a select group of clients.”

Source: company website · checked Sep 6, 2026
8Strong evidenceWashington, DC, United StatesHQ checked Sep 6, 202611-5027 contacts →

“Webster, Chamberlain & Bean, LLP is the leading law firm in the United States specializing in the provision of a full range of legal services to tax-exempt organizations.”

Source: company website · checked Sep 6, 2026
9Partial evidenceWashington, DC, United StatesHQ checked Sep 6, 202611-5026 contacts →

“Beginning in 1955, GKG Law remains dedicated to crafting the best approach to meet our clients’ needs.”

Source: company website · checked Sep 6, 2026
10Indirect evidenceWashington, DC, United StatesHQ checked Sep 6, 202611-5020 contacts →

“Built on decades of experience and a deep commitment to our long-standing clients, our attorneys guide clients through all aspects of their largest, most sensitive and critical…”

Source: company website · checked Sep 6, 2026
11Partial evidenceWashington, DC, United StatesHQ checked Sep 6, 202611-5017 contacts →

“Kalbian Hagerty LLP is an international general practice law firm with offices in Washington, D.C, Abu Dhabi, U.A.E, and New York City and a strategic alliance with a prominent…”

Source: company website · checked Sep 6, 2026
12Partial evidenceWashington, DC, United StatesHQ checked Sep 6, 202611-5017 contacts →

“RoseMcKenna PLLC is a boutique accounting firm dedicated to providing the absolute best in personalized and professional tax services.”

Source: company website · checked Sep 6, 2026
13Indirect evidenceWashington, DC, United StatesHQ checked Sep 6, 202611-5016 contacts →

“CWP Consulting was built around the desire to provide quality, professional services to individuals and business owners through the use of specialized and individualized services.”

Source: company website · checked Sep 6, 2026
14Partial evidenceWashington, DC, United StatesHQ checked Sep 6, 20261-1016 contacts →

“A full-service business law firm, Veritas Law has expertise in corporate and transactional law, litigation, and licensing.”

Source: company website · checked Sep 6, 2026
15Indirect evidenceWashington, DC, United StatesHQ checked Sep 6, 202611-5014 contacts →

“Founded in 1964, we are a Washington, D.C.”

Source: company website · checked Sep 6, 2026
16Partial evidenceWashington, DC, United StatesHQ checked Sep 6, 202611-5012 contacts →

“WATKINSON MILLER PLLC is a law practice company based out of 1100 New Jersey Ave SE Suite 910, WASHINGTON, District of Columbia, United States.”

Source: company website · checked Sep 6, 2026
17Indirect evidenceWashington, DC, United StatesHQ checked Sep 6, 202611-5012 contacts →

“At Basswood Counsel, we believe that we should be as dynamic and growth-oriented as the companies we serve.”

Source: company website · checked Sep 6, 2026
18Strong evidenceWashington, DC, United StatesHQ checked Sep 6, 202611-5010 contacts →

“Rosefelt Tax Law is a Washington, DC Metro-based firm with a national practice representing clients with serious tax problems and financial concerns.”

Source: company website · checked Sep 6, 2026
19Partial evidenceWashington, DC, United StatesHQ checked Sep 6, 20261-1010 contacts →

“The Royal Law Firm PLLC, founded in 2009 by Priya Prakash Royal, Esq, LL.M, MBA, AEP®, TEP, is a private client law firm serving individuals, families, and closely held…”

Source: company website · checked Sep 6, 2026
20Indirect evidenceWashington, DC, United StatesHQ checked Sep 6, 20261-107 contacts →

“For over three decades, Alan S.”

Source: company website · checked Sep 6, 2026
21Partial evidenceWashington, DC, United StatesHQ checked Sep 6, 202611-506 contacts →

“In 2001 Capitol Tax Partners’ founders relied on decades of government experience to create Washington’s premier tax firm that could provide clients with both political and tax…”

Source: company website · checked Sep 6, 2026
22Strong evidenceWashington, DC, United StatesHQ checked Sep 6, 20261-105 contacts →

“Pontius Tax Law, PLLC represents individual and business clients with sensitive and serious tax matters before the Internal Revenue Service and state taxing authorities.”

Source: company website · checked Sep 6, 2026
23Indirect evidenceWashington, DC, United StatesHQ checked Sep 6, 202611-505 contacts →

“Welcome to the firm of”

Source: company website · checked Sep 6, 2026
24Partial evidenceWashington, DC, United StatesHQ checked Sep 6, 20261-105 contacts →

“Musolino & Dessel PLLC is a boutique law firm based out of 1615 L St NW #440, Washington, D.C.”

Source: company website · checked Sep 6, 2026
25Indirect evidenceWashington, DC, United StatesHQ checked Sep 6, 20261-105 contacts →

“Washington DC Business Lawyer Large-Firm Results with Boutique-Firm Attention At Tobin, O’Connor & Ewing, we focus on providing our clients with effective representation and…”

Source: company website · checked Sep 6, 2026

Showing 25 of 86 tax law firms based in Washington, United States

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Tax law firms based in Washington, United States at a glance

As of Sep 6, 2026
63.5%Verified-email coverage
88.5Average contacts per company
1-10Median size (employees)
576.7%Largest-city concentration · New York
Sep 6, 2026Page data refreshed

Companies by employee count

1-10
49
11-50
25
51-200
8
501-1,000
1
1,001-5,000
3

Email recency for this list is measured across the whole United States list rather than this city, so it is reported there. Company counts and contact totals on this page are exact for Washington, over 86 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 tax law 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 Washington, United States whose own description of what they do matches “tax law 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 tax law 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 tax law firms, and records with no verified work email. Companies headquartered outside Washington 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, 4,829 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 6, 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.

Tax law firms by metro in the United States

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 tax law 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 tax law firms are there based in Washington, United States?

RevenueBase identified 86 tax law firms headquartered in Washington, 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?

Arnold & Porter, headquartered in Washington, tops this list with the largest team on record.

Which city has the most tax law firms?

New York leads with 496 headquartered companies, followed by Houston (274) and Chicago (259).

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 4,829 verified decision-maker contacts tracked across these 86 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 6, 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.