Company lists · Data refreshed September 2026
Top 24 O-1 visa law firms based in London, United Kingdom
RevenueBase identified 62 o-1 visa law firms headquartered in London, United Kingdom as of September 2026 and tracks 335 professional contacts across them, including 81 with verified work emails. Across the United Kingdom, London is the largest hub for this category.
This list covers o-1 visa law firms headquartered in London, United Kingdom, 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 29, 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.
The 24 largest o-1 visa law firms based in London, United Kingdom
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 24 contacts → | ||||
Partial evidence “Public Law 2.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 2 | 22 contacts → | ||||
Indirect evidence “At Samartin & Friends, we specialise in helping people and businesses navigate the often complex process of U.S.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 3 | 16 contacts → | ||||
Partial evidence “Welcome to NARA Solicitors, a modern law firm with a commitment to delivering exceptional legal services, operating under the regulation of the Solicitors Regulation Authority.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 4 | 16 contacts → | ||||
Partial evidence “M-R Solicitors LLP is one of the top UK law firms providing services to large portfolio of clients in private and business sector from last 14 years.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 5 | 13 contacts → | ||||
Strong evidence “Flynn Hodkinson is a boutique US visa and nationality law practice based in the UK and Ireland.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 6 | 11 contacts → | ||||
Indirect evidence “SKY SOLICITORS LTD is a company based out of 60 HIGH ROAD LEYTON, LONDON, United Kingdom.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 7 | 9 contacts → | ||||
Partial evidence “SMK Law Solicitors specialise in immigration, asylum and human rights law.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 8 | 6 contacts → | ||||
Partial evidence “Brill Immigration is a US immigration law firm based in London’s Fitzrovia serving some of the world’s best creatives and entrepreneurs, multinational businesses, film and…” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 9 | 6 contacts → | ||||
Indirect evidence “From offices in the US and the UK, NNU Immigration is a leading firm of US immigration attorneys, advising global businesses, entrepreneurs and high net-worth private clients…” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 10 | 5 contacts → | ||||
Partial evidence “With decades of experience and an exceptionally high success rate in family and immigration law, you can trust Osbourne Pinner with your case.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 11 | 5 contacts → | ||||
Indirect evidence “Ortega-Medina & Associates is a firm of United States business immigration lawyers, with associated offices in London, San Francisco and Miami Beach.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 12 | 5 contacts → | ||||
Partial evidence “At the heart of WestBridge is a dedicated team of immigration and employment law experts with over 13 years of experience, offering tailored legal solutions to businesses of all…” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 13 | 5 contacts → | ||||
Indirect evidence “At Bukhari Chambers we strive to provide holistic solutions that directly respond to our clients' individual needs.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 14 | 4 contacts → | ||||
Indirect evidence “A EJR Legal Services tem um procedimento rigoroso para garantir que cada caso seja submetido a uma avaliação inicial completa com nosso profissional especializado em imigração.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 15 | 4 contacts → | ||||
Indirect evidence “Leading Immigration & Family Lawyers in London” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 16 | 3 contacts → | ||||
Partial evidence “Meymand Maczynski is a trusted boutique business immigration law firm in Mayfair regulated by the Solicitors Regulation Authority and recognised as a leading firm in the Legal 500.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 17 | 3 contacts → | ||||
Partial evidence “A law firm based in London, covering primarily Immigration, Litigation, Employment and Family | Call us on 020 8543 3938.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 18 | 3 contacts → | ||||
Partial evidence “D'Ascanio Law is a national Immigration Law Firm dedicated to meeting the unique needs of our clients.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 19 | 3 contacts → | ||||
Indirect evidence “Based in London and active internationally, we provide bespoke immigration solutions for both business and personal matters.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 20 | 3 contacts → | ||||
Partial evidence “Chavin Immigration Law Office is the solo immigration law practice of Melissa Chavin, Attorney.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 21 | 2 contacts → | ||||
Partial evidence “The American Immigration Law Office is based in the heart of London, UK.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 22 | 1 contacts → | ||||
Partial evidence “B&A Immigration is a United States Immigration law firm based in London, United Kingdom.” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 23 | 1 contacts → | ||||
Indirect evidence “Recognised by both Legal 500 & Chambers and Partners, we excel at providing bespoke immigration advice to a select number of corporate and private clients who demand a…” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
| 24 | 1 contacts → | ||||
Indirect evidence “Grovelands Immigration is a dedicated immigration specialist providing expert legal services and strategic advice to both corporate and individual clients across a range of…” Source: RevenueBase Database · checked Sep 29, 2026Thanks. The Data Team will review it. | |||||
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: o-1 visa law 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 o-1 visa law firms.
- Partial evidence
- Its own public description names part of o-1 visa law firms, so it works in or next to the category without describing itself that way.
- Indirect evidence
- The description shown does not name o-1 visa law 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 24 of 62 o-1 visa law firms based in London, United Kingdom
See the full list, filter by size, metro and specialty, and get verified emails and direct dials for all 81 reachable decision-makers.
Free signup · no credit card
O-1 visa law firms based in London, United Kingdom at a glance
As of Sep 29, 2026Companies by employee count
Email recency for this list is measured across the whole United Kingdom list rather than for London, so it is reported there. Company counts and contact totals on this page are exact for London, over 62 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 o-1 visa 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 London, United Kingdom whose own description of what they do matches “o-1 visa 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 o-1 visa 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 o-1 visa law firms, and records with no verified work email. Companies headquartered outside London 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, 81 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 29, 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.
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 o-1 visa 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 o-1 visa law firms are there based in London, United Kingdom?
RevenueBase identified 62 o-1 visa law firms headquartered in London, United Kingdom 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?
S. A. J Legal, headquartered in London, tops this list with the largest team on record.
Which city in the United Kingdom has the most o-1 visa law firms?
London leads the United Kingdom with 62 headquartered companies, followed by Birmingham (9) and Manchester (6).
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 81 verified decision-maker contacts tracked across these 62 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 29, 2026.
Ready to reach these companies? Verified emails and direct dials for all 62 o-1 visa law firms based in London, United Kingdom. Start with a free account, no credit card.
Download this list →Related lists
O-1 visa law firms by geography
- O-1 visa law firms based in Toronto, Canada
- O-1 visa law firms based in Atlanta, United States
- O-1 visa law firms based in Austin, United States
- O-1 visa law firms based in Boston, United States
- O-1 visa law firms based in Chicago, United States
- O-1 visa law firms based in Dallas, United States
- O-1 visa law firms based in Houston, United States
- O-1 visa law firms based in Los Angeles, United States
- O-1 visa law firms based in Miami, United States
- O-1 visa law firms based in New York, United States
- O-1 visa law firms based in Orlando, United States
- O-1 visa law firms based in Philadelphia, United States
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.
More company lists
- All company lists
- Lists by location
- Lists A-Z
- New lists
- O-1 visa law firms based in Toronto, Canada
- O-1 visa law firms based in Atlanta, United States
- O-1 visa law firms based in Austin, United States
- O-1 visa law firms based in Boston, United States
- O-1 visa law firms based in Chicago, United States
- O-1 visa law firms based in Dallas, United States