Joseph Hage Aaronson LLP > London, England > Firm Profile

Joseph Hage Aaronson LLP

Dispute resolution > Tax litigation and investigations Tier 1

Boutique contentious tax firm Joseph Hage Aaronson LLP is well known for its expertise in complex domestic and cross-border tax disputes, including litigation, arbitration, and investigations. The department is jointly led by founding partners Michael Anderson, a highly experienced litigator with a specialism in the taxation of cryptocurrencies, and Graham Aaronson KC, who has expertise in transfer pricing, oil and gas taxation, and EU law. Also key are Simon Whitehead, who has over 35 years’ litigation experience, Paul Farmer, who has a broad background in European and international tax law, and Iain MacWhannell, who acts for a diverse and high profile client base of individuals, businesses, and trusts. Solicitor and chartered tax advisor Helen McGhee and Daniel Margolin KC are further core team members.

Practice head(s):

Graham Aaronson KC; Michael Anderson


‘JHA is the only significant sized law firm that focuses on tax litigation (as opposed to simply being a tax department in a multi-service firm). It can properly be said, then, that they are true tax litigation experts. They are therefore always in the running (and likely in the lead) for any major tax controversy work.’

‘Iain MacWhannell is a star individual. His attention to detail is remarkable, and he has a real feel for litigation tactics (and an uncanny ability to predict what HMRC’s next move will be). Daniel Margolin KC is a class act. Measured, considered and smooth.’

‘The key strengths are the bespoke service afforded to the client as well as the attention to detail. The team also deliver a fully connected end-to-end strategy which takes account of all the pitfalls of litigation.’

‘Simon Whitehead is truly a leader in his field. His ability to create solutions to potential issues is extremely helpful. He is always available and is extremely supportive of the clients he looks after. He also delivers a top quality product and puts the client in the best possible position from a litigation standpoint.’

‘The team that I have worked with at JHA is very responsive and has very good common sense with regard to the most practical way to find a satisfactory resolution to a conflict. I think that there are many teams that are able to provide correct advice as to the actual issues at hand, but it is rare to find one which does such a good job of thinking commercially and pragmatically.’

‘Fantastically experienced team cornering the market for tax GLO work.’

‘Simon Whitehead is very easy to work with and has always been happy to share his extensive knowledge and experience.’

‘JHA are extremely responsive to our queries and excellent at summarising and explaining difficult technical concepts. In addition, JHA also consider the commercial aspect when providing advice.’

Key clients

British American Tobacco PLC

Marks & Spencer Group PLC

Prudential PLC


Ford Motor Company (FCE Bank PLC)

EMI Group Limited (Universal Music Group)

GKN Aerospace Limited

Fidelity International


Prudential PLC

Work highlights

  • Advised 25 UK headquartered multinationals in their challenge to the UK’s dividend taxation scheme.
  • Represented over 18,000 companies in their appeals to the Tax Tribunal against assessments to VAT, National Insurance Contributions, and VAT de-registration.
  • Pursued Closure Notice Applications in the First-Tier Tribunal on behalf of a group of approximately 180 taxpayers who are seeking repayment of unlawfully levied tax on foreign portfolio dividend income.

The firm: Our Clients’ needs are at the heart of JHA’s business; our unique structure was born out of a belief that an effective case strategy could be delivered more efficiently if lawyers, barristers, and forensic accountants worked side by side from the outset.

We combine the qualities of a traditional law firm with that of a chambers. Solicitors and barristers, with their distinctive training and experience, work closely as an integrated team to discuss and devise strategy together from the outset to meet our clients’ aims, whether via litigation, arbitration, mediation or settlement.

This simple precept has enabled us to attract and retain numerous clients, many of whom have come to rely on us as a trusted partner to manage and settle their complex disputes.

All clients have full and easy access to the whole legal team from the initial meeting onwards. We provide timely advice and the efficient delivery of a well-considered and effective case strategy. We build close relationships with our clients, based on mutual trust and a deep understanding of their commercial and legal objectives. We are highly sensitive to our clients’ need for privacy and never seek to promote our own business based on their success.

JHA is ranked in Tier 1 in the Legal 500 UK for Tax Litigation and Investigations and is recognised as the only top tier firm for Contentious Tax by Chambers UK. These accomplishments have been achieved every year since the firm was founded in 2013.

Types of work undertaken:

Tax Disputes: JHA’s contentious tax practice brings together barristers, solicitors, chartered tax advisors, and accountants. Together, we deliver a cohesive, considered and effective approach to advising and representing clients through all stages of a dispute.

Our practice is ranked in Tier One of Legal 500 and is the only group to be ranked in Band One in the Chambers UK guide. We have achieved this top tier recognition every year since the firm’s inception.

We act on a wide range of domestic and international tax disputes, advising multinational corporations on various corporation tax disputes with HMRC. This includes acting in all but one of the Group Litigation Orders (GLOs) challenging various elements of the UK’s tax legislation as being contrary to EU law.

In more recent years, JHA has also built a strong reputation for our tax fraud/abuse and tax investigations work, including our role as lead and test case solicitors in the largest VAT Group Litigation that has ever taken place in the Tax Tribunal.

Transfer pricing disputes is a further area of expertise; we are experienced at dealing with HMRC enquiries and investigations and have been active in the highest profile and value transfer pricing disputes of recent years, including those involving Diverted Profits tax. This is an area we have been advising on since its introduction and we are proficient at reaching settlements with HMRC, including in obtaining significant penalty reductions.

Our team also represents entrepreneurs and owner-managed businesses on sensitive or difficult tax disputes as well as high net worth individuals facing enquiries and criminal investigations. We work to resolve tax disputes through proactive cooperation and engagement with HMRC, resulting in a constructive working relationship, which enables us to deliver a high proportion of positive outcomes for clients.

Department Name Email Telephone
Joe Hage +44 (0)20 7851 8888
Graham Aaronson KC +44 (0)20 7851 8888
Photo Name Position Profile
Graham Aaronson photo Graham Aaronson Graham Aaronson KC is a founding partner of Joseph Hage Aaronson LLP…
Michael Anderson photo Michael Anderson Michael has been a partner at JHA since its inception. He has…
Steve Bousher photo Steve Bousher Senior Associate dealing with a wide range of tax disputes including: representing…
Paul Farmer photo Paul Farmer Paul Farmer is a Barrister and was a founding partner in Joseph…
Joseph Irwin photo Joseph Irwin Joseph qualified as an associate at JHA in December 2017. His practice…
Jill Kaur photo Jill Kaur Jill is a Chartered Tax Adviser with 25 years’ experience in the…
Iain MacWhannell photo Iain MacWhannell Iain was called to the Bar in 2006 and his practice focuses…
Daniel Margolin photo Daniel Margolin Daniel was called to the Bar in 1995 and appointed Queen’s Counsel…
Ray McCann photo Ray McCann Ray is a Fellow of the Chartered Institute of Taxation and was…
Helen McGhee photo Helen McGhee Helen is a Partner in the Joseph Hage Aaronson contentious tax team…
Simon Whitehead photo Simon Whitehead Simon Whitehead was a founding partner of the firm. He has more…
Photo Name Position Profile
Megan Durnford photo Megan Durnford Megan was called to the Bar in 2016 and her practice is…

At Joseph Hage Aaronson our commitment to diversity and inclusion, responsible businesses, and having a positive impact on our community is entrenched in our culture. This is reflected in our firm values of commitment, inclusiveness, creativity, and integrity.

We believe a diverse and inclusive community encourages a stimulating, rewarding and inventive working environment. For these reasons, we are committed to creating a welcoming workplace in which all our people can thrive, regardless of their characteristics, beliefs, and preferences. We monitor diversity statistics to ensure that our practices are fair and non-discriminatory. This means we are best positioned to continue to provide our clients with a first-class service.

Our pro bono work, sponsorships, and charitable giving enable us to help and support individuals and organisations with limited access to resources and opportunities. It also means our people can share their experience and expertise in support of causes which can have a positive and lasting impact on our community.

The two main charities we support are Access2Justice and the children’s charity Variety. Access2Justice provides legal services support to those who need it the most, particularly the ill, injured and economically disadvantaged. Variety helps to change the lives of children throughout the UK who are sick, disabled or underprivileged, through providing specialist coaching, equipment or experiences, and by supporting hospitals and youth centres.

We also encourage many of our employees to actively support their own charitable initiatives and we make financial contributions to their chosen causes.

JHA is a passionate supporter of the arts and is involved in many initiatives that support artists and nurture new talent in the art world. Education is also a key focus and we sponsor educational programmes and training.

The firm supports staff in providing pro bono support or undertaking voluntary work. All solicitors and barristers at JHA are given an allowance of 40 hours from their working year to participate in either voluntary or pro bono work. Employees in support functions can devote 20 hours of working time to voluntary work each year.