Hearts & Minds: A millionaire migration myth?

The next time the comms team is asked to work on a data-led report, you might wish to quiz the compilers and check their methodology before sending the press release.

Henley & Partners recently published its annual Wealth Migration Report claiming a net 16,500 millionaires were leaving the UK as a result of tax changes. It was a lead news item, published and referenced all over. The survey has previously been hailed as influential, a key driver in guiding thinking about strategies and trades regarding the wealthy.

No longer. This year, thanks to the attention heaped on the impact of Labour’s Budget and constant claims of rich folks, especially non-doms, exiting the UK, the findings received closer scrutiny than usual. Politicians and the press were quick to challenge their validity. Alas, they were quickly debunked by the ex-tax lawyer and commentator Dan Niedle and his think tank, Tax Policy Associates and the FT. They were able to demonstrate that not only was the data inaccurate, but worse, the company knew it was misplaced for some years and took no corrective action. ‘The best-known survey on the topic comes annually from Henley & Partners, with data from New World Wealth, a consultancy in South Africa. It claims to calculate net millionaire migration for many countries. The UK came bottom of this league in 2025, with a net 16,500 millionaires said to be fleeing Reeves’ tax grabs,’ wrote the FT. But then this: ‘Neither Henley & Partners, which advises people seeking residency and citizenship abroad, nor anyone else can know how many millionaires are leaving the UK because the data simply does not exist.’ Ouch.

It turned out that the information on tax residency was partially drawn from LinkedIn – which does not provide any detail on tax residency (but relies on job role location). Tax Policy Associates said: ‘Until an independent audit is carried out, the Wealth Migration Report should be treated as marketing material not evidence.’

This may mark the beginning of more scrutiny into the many marketing-led reports that are published every year in the hope of securing extra column inches. Before you approve the press release, please make sure you have looked at the data and methodology, go behind the analysis and what exactly is being claimed, to make sure it will not do the company, the brand, yourselves, more harm than good. Let the Wealth Migration Report be a warning.

Chris Blackhurst is one of the UK’s foremost business journalists. He was previously Editor of The Independent and City Editor of the Evening Standard.