Addison Lee Founder Loses Non-Dom Claim and Owes £20.5m in Tax
John Griffin, the founder of Addison Lee, owes an additional £20.5m in UK tax for a seven-year period after a London tax tribunal dismissed his claim to be treated as non-domiciled and ruled in favour of HMRC. The Guardian
The dispute centred on his self-assessment tax returns from 2013 to 2020. Self-assessment is the system where taxpayers report their own income to HMRC, the UK tax authority. HMRC challenged the domicile status declared in those returns. The tribunal rejected Griffin's position.
Domicile is the legal idea of a permanent home for tax purposes. A non-domiciled, or non-dom, person lives in the UK but claims a permanent home in another country. That claim once allowed different tax treatment. It is like arguing your home base is elsewhere, even while you live and work in London.
Griffin was born to Irish parents in 1942 and moved to London at age nine. He founded Addison Lee in 1975. He sold the business to the Carlyle Group in 2013, when it was reported to be worth £300m. He was knighted in 2024 for services to business and charity.
His argument rested on paternal descent. He said his domicile should follow that of his father Jack, who came to England from Ireland in 1935. The tribunal found otherwise. It held that by 5 April 2013 Griffin had settled in England in every meaningful sense.
The hearing tested that finding against his time in Ireland. The tribunal was told he spent eight nights in Ireland in 2015, one of the years for which he claimed Irish domicile. Griffin did not give evidence in person. HMRC accepted he was not medically fit to do so due to cognitive decline. The outcome applies to the returns before it and leaves him liable for the additional tax.
The broader context here is the end of the regime on which his claim depended. The Labour government scrapped UK non-dom status in April 2025. For tax specialists, the interest is in method. Domicile turns on facts examined year by year. Tribunals give limited weight to a stated claim of foreign domicile when conduct points toward settlement in England. Presence matters, and eight nights in the claimed country in a tax year is a weak foundation once settlement in England is found.
In my view, advisers will read this ruling as confirmation. Seven tax years were examined together, so liabilities built up into a very large sum. Abolition does not erase that history. Cases rooted in pre-2025 returns will continue to be decided on their own facts, with the burden on the taxpayer to answer HMRC's challenge. Historic non-dom positions remain testable, costly to defend, and vulnerable where day-to-day life has long been centred in England.
