Old Square Tax Chambers

What Old Square Tax Chambers does

Old Square Tax Chambers is a London-based barristers' chambers operating from 15 Old Square, Lincoln's Inn, founded in 1964 and specialising exclusively in UK taxation and revenue law. The chambers is one of the leading UK tax sets, ranked Band 1 by Chambers and Partners and tier 1 by Legal 500, and was named Tax Set of the Year at the 2022 Chambers UK Bar Awards. Its members — including senior KCs such as Rory Mullan KC (current Head of Chambers and Chair of the Revenue Bar Association), James Kessler KC, and Robert Venables KC — provide advisory, drafting, and litigation services across the full spectrum of UK tax law, including corporate tax, personal and private client tax, inheritance tax, VAT, customs and excise, stamp duty land tax, non-domicile and residency issues, trusts and estates, and HMRC enquiries and investigations, with advocacy extending from the First-tier Tribunal through to the Supreme Court and Privy Council.

The chambers' core products are professional legal services billed as counsel fees on a per-matter or per-brief basis, supplemented by educational content (seminars, webinars, the TaxSnax short-form video series, and the International Tax Bites podcast) and textbook authorship that reinforces its thought-leadership position. There is no proprietary technology platform or software product; the underlying capability is human legal expertise, with the clerks room acting as the central coordination hub for matching instructing professionals (solicitors, accountants, and tax advisers) and authorised Direct Access lay clients to the appropriate barrister. The business is a private professional association rather than a corporate entity, with no external investors, no parent company, and no subsidiaries, and it is regulated by the Bar Standards Board.

Revenue is generated entirely through barrister fees for advisory and litigation work, with pricing negotiated per matter and not publicly disclosed. The go-to-market motion is sales-led and intermediated: instructions flow primarily through professional advisers, with a secondary Direct Access channel for lay clients. End customers span high-net-worth individuals, businesses and organisations, charities and trusts, and international/non-resident clients with cross-border tax needs, serving both UK domestic and global matters. The chambers sustains its position through an active seminar and publication programme (including the long-running Key Haven Practical Tax Planning residential seminar at Oxford) and consistent recognition in legal directories and industry awards.

Name

Old Square Tax Chambers

Legal name

Old Square Tax Chambers

Website

https://taxchambers.com

Company type

Private

Founded year

1995

Operating status

Operating

Headcount range

11–50 employees

Short description

Old Square Tax Chambers is a London-based barristers' chambers specialising in UK taxation and revenue law, advising high-net-worth individuals, businesses, charities, and international clients on tax planning, litigation, and HMRC disputes, with advocacy from the First-tier Tribunal to the Supreme Court.

Ownership category

akta.pro rank

Product category

Tax Law Legal Services

NAICS

Legal Services (5411), Offices of Lawyers (54111), Offices of Lawyers (541110)

SIC

Services-Legal Services (8111)

akta.pro primary industry

Tax Law (BPAHAAAG)

akta.pro secondary industries

Family & Private Client (Trusts & Estates) Law (BPAHAAAK), Trust & Estate Tax Planning & Compliance (FSAEAKAE), Dispute Resolution, Appeals & Tax Tribunals (BPAIADAK)

Keywords

• Tax litigation services
• Barrister chambers
• Tax advisory counsel
• Private client tax
• Tax tribunal representation

Headquarters

HQ city

London

HQ country

United Kingdom

HQ region

Europe

Offices1 record

Markets served

GTM type

B2B

Offering type

Services

Cost components

Personnel, Operations, Marketing or Sales, Technology or R&D, Infrastructure

Revenue model

1. Legal Services - Barrister Fees: Chambers generates revenue through barristers charging fees for legal advisory, representation, and litigation services in all areas of UK taxation and revenue law. Fees are typically billed per matter, per hearing, or on an agreed-fee basis. Individual barristers invoice clients (via instructing solicitors or directly under Direct Access) for counsel fees, advice work, drafting, and tribunal/court appearances.

Go-to-market motion1 record

Distribution channels3 records

Marketing channels8 records

Core offering

Old Square Tax Chambers is a London-based barristers' chambers providing specialist legal advice, advocacy, and representation across all areas of UK taxation and revenue law. Members act as counsel in tax planning, HMRC enquiries and investigations, tribunals (First-tier, Upper), the Court of Appeal, Supreme Court, and Privy Council, and accept direct instructions from lay clients under the Direct Access scheme.

Product overview

Old Square Tax Chambers is a leading barristers' chambers specializing in UK taxation and revenue law. The chambers provides specialist expertise across all areas of taxation through its team of barristers offering legal advice, representation, and advocacy services. Services include advisory work, tribunal and court representation, and public access instructions. The chambers does not operate a software platform but provides professional legal services delivered by individual barristers.

Differentiator

Problem solved

Functional benefit

Products and services

• Tax Advisory Services Specialist legal advice from barristers covering all areas of UK taxation including corporate tax, personal tax, inheritance tax, VAT, stamp duty land tax, non-resident/non-domicile tax, and international tax matters, provided to instructing solicitors, accountants, and other professional advisers.
• Tax Litigation and Appeals Advocacy and representation by barristers in HMRC enquiries and investigations, First-tier Tribunal, Upper Tribunal, Court of Appeal, Supreme Court, and Privy Council across the full spectrum of tax disputes.
• Direct Access (Public Access Scheme) Service allowing authorised members of chambers to accept instructions directly from lay clients (members of the public) under the Bar Council's Direct Access scheme, without the need for an intermediary solicitor or accountant.
• TaxSnax Video Series

Quantifiable outcome

• Old Square Tax Chambers members have appeared in landmark cases before the Supreme Court (e.g., Fisher v HMRC [2023] UKSC 44), Court of Appeal, Upper Tribunal, and First-tier Tribunal across a broad spectrum of tax law.

Segments4 records

Ideal customer profiles3 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Partnerships

Four partnerships are on record, tiered core and minor.

• Key Haven Publications LtdcoreStrategic or Co-development PartnerKey Haven Publications Ltd collaborates with Old Square Tax Chambers on the annual Practical Tax Planning residential seminar held at Merton College, Oxford. This is the 37th-42nd annual iteration of the seminar. Key Haven organises and markets the event while chambers members serve as primary speakers. The partnership positions chambers as a thought leader in tax planning and provides a significant client-facing and professional networking platform.
• Chambers and PartnersminorOthersChambers and Partners is a legal directory that independently ranks Old Square Tax Chambers. The chambers displays Chambers and Partners logos on its homepage indicating its ranking status. This is a third-party endorsement/referencing relationship.
• Legal 500minorOthersLegal 500 is an independent legal directory that ranks Old Square Tax Chambers and its members. The chambers references its Legal 500 rankings on its website.
• Temple Tax ChambersminorOthersKeith Gordon, who practices from Temple Tax Chambers (3 Temple Gardens, London EC4Y 9AU), is listed as a speaker at the Key Haven/Old Square Tax Chambers Practical Tax Planning seminar alongside chambers members. This is a speaker/co-presenter relationship.

Scale indicators1 record

Recent moves6 records

Expansion highlights4 records

Broad incumbents

• Macfarlanes LLP: Magic Circle law firm with a leading private-client tax practice that both competes with barristers' chambers (solicitor-side tax advice) and instructs counsel at Old Square; a key counterparty in the intermediary ecosystem.
• Withers Worldwide: International law firm highly active in private-client tax, trusts and estate planning for HNW individuals; overlapping client base with Old Square and a frequent instructing firm for the chambers.
• Twenty Essex: Large London barristers' chambers with a multi-disciplinary offering including tax; broader and less tax-specialised than Old Square but a comparable destination for high-value tax disputes from instructing solicitors.
• Mishcon de Reya LLP: London law firm with a substantial private-client and tax practice; both a competitor for advisory mandates and a source of instructions for specialist tax counsel at Old Square.
• Clifford Chance LLP: Global Magic Circle firm with a significant corporate tax and tax disputes practice; represents large corporates and financial institutions that occasionally become instructing clients or opposing parties in Old Square's litigation work.

Direct peers

• Temple Tax Chambers: Specialist tax barristers' chambers at 3 Temple Gardens, London. Co-presents with Old Square members at the Key Haven Practical Tax Planning seminar and competes for similar private-client and trust tax briefs.
• Pump Court Tax Chambers: One of the principal UK tax barristers' sets, also based in London and ranked alongside Old Square in Chambers & Partners and Legal 500 for tax advisory and litigation. Direct head-to-head competitor for the same instructing solicitors and accountancy firms.
• 11 New Square: Established London barristers' chambers with a strong tax and trusts practice that overlaps materially with Old Square on private client, IHT and trust disputes. Ranked in the same legal directories.
• Gray's Inn Tax Chambers: London tax barristers' set offering advisory and litigation across personal, corporate and indirect tax. Appears in the same Chambers & Partners and Legal 500 rankings and is a direct substitute for instructing professionals.
• Field Court Tax Chambers: London-based tax barristers' chambers with comparable practice mix spanning personal tax, corporate tax, VAT and tax litigation. Regularly cited in the same Chambers & Partners and Legal 500 rankings as a competing set.

Market position

Strengths4 records

Weaknesses4 records

Competitive moat4 records

Key risks5 records

Key highlights6 records

Customer concentration

• Xx.com/OldSquareTax
• LinkedInlinkedin.com/company/tax-chambers

Revenue estimate

Valuation estimate

Number of profiles

Profiles2 records

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Old Square Tax Chambers