Thank you for taking the time to engage with the article. You raise several points worth addressing:

*On non-dom status:* You’re absolutely right that the old non-dom regime was indefensible as policy. The idea that someone could live in Mayfair for decades, contribute significantly to the UK economy and society, yet structure their affairs to avoid UK tax on worldwide income was indeed absurd. Lord Rothermere is the perfect example of the inequity. My point wasn’t to defend non-doms, but to note that their departure represents a revenue loss - which it objectively does, regardless of whether the previous regime was justifiable.

However, I’d push back on your characterisation that their only contribution was “Mayfair lunch bills and maids.” Many non-doms were significant employers, investors in UK businesses, property owners paying substantial SDLT and council tax, and contributors to UK charities and institutions. The departure of 1,800 people (50% above OBR forecasts) does represent a genuine fiscal impact beyond lunch bills.

*On CGT rates:* Here you’re on shakier ground. You say “it was tomfoolery having it at 10%” and claim this was the “lowest by far amongst industrialised countries.” That’s simply not accurate. Looking at OECD data:

- Switzerland: 0% (cantonal taxes vary but often much lower than UK) - Belgium: 0% on shares - New Zealand: 0% in most cases - Luxembourg: 0% after 6 months - Netherlands: effective rate often under 10% - Germany: 26.4% but only on recent gains

The UK’s 10% rate for BADR was competitive but hardly an outlier. And your claim that “no founders have ever” made decisions based on tax planning simply doesn’t match reality. Talk to any M&A advisor or tax accountant - timing of exits around tax changes is absolutely a consideration for founders and investors. It may not be the primary driver, but it’s certainly a factor in a multi-million pound decision.

*On asset prices explaining the CGT decline:* This is a fair point worth examining. You’re correct that CGT receipts are volatile and correlate with asset prices. However, the OBR itself attributed the shortfall to factors beyond just asset price movements - they specifically noted behavioural responses and structural changes. The 19% decline from £16.9bn to £13.7bn over two years occurred during a period when equity markets were actually relatively stable or rising (FTSE 100 up, property prices mixed but not collapsing). If it were purely asset prices, we’d expect to see similar patterns in other countries with buoyant markets - but we don’t.

*On international competition examples:* You dismiss Dubai as a “complete red herring” but that’s where the wealthy are actually going - 9,800 millionaire inflows projected. Whether you or I like it is irrelevant; it’s happening. On Portugal, yes, they’ve tightened some golden visa rules, but they remain significantly more attractive than the UK for many tax purposes. And on Ireland, I deliberately picked corporation tax because that’s the rate that matters most for business location decisions - which is precisely what we’re discussing.

*The fundamental point:* You can argue about whether individual tax changes were justified on equity grounds (and I’d agree with you on non-doms), but that’s separate from whether they’re producing the revenue forecasted. The OBR’s £7.5bn shortfall is a fact, not opinion. The 50% higher-than-forecast non-dom departures are measurable. The CGT revenue decline is in the data.

Whether these policies are morally right is one question. Whether they’re achieving their fiscal objectives is another. The evidence suggests they’re not - and that’s the Laffer curve dynamic in action, regardless of how we feel about the underlying fairness of previous regimes.

What’s your view on the broader revenue shortfall and the OBR’s structural deficit assessment?

I won't belabour the non-doms point as you concede yourself it was indefensible.

On CGT comps - all those are not straight forward. You can have Switz, NZ, and Bel. You can't have Lux (22% if hold >10%) or Netherlands (the system is mental... - they get their 30% though)

I think the bulging argument against the 19% two year decline is the first of those years you cite was before the labour govt, and before any changes?

Fair points on the CGT comparisons - you’re right that some of those systems are more complex than headline rates suggest. Luxembourg and Netherlands do have their quirks.

But on the timing point - that’s actually my exact argument. The 19% CGT decline from £16.9bn (2022-23) to £13.7bn (2024-25) happened BEFORE Labour’s October 2024 rate increases. The decline occurred under the Conservative government while rates were still at the “low” levels you criticised.

That’s precisely the problem: revenues were already falling when rates were at 10%/20%. Then Labour increased them to 18%/24% in October 2024, likely accelerating the decline further (we’ll see in the next fiscal year’s data).

So the revenue decline can’t be blamed on Labour’s rate increases - it happened before them. Which suggests either:

1. Even the “low” rates were still high enough to trigger behavioural responses, or 1. Other factors (non-dom changes announced, anticipated tax increases, international competition) were already driving capital flight

Either way, it supports the Laffer curve thesis: the tax base was shrinking before the rate increases, and those increases are unlikely to reverse the trend.

The OBR’s £7.5bn shortfall report (March 2025) specifically attributes this to behavioural factors beyond just asset prices, which is why they classified £4.5bn as structural rather than temporary.

What’s your read on why CGT revenues fell 14% in 2023-24 if rates hadn’t changed yet?

Oh you've lost connection with your Laffer Curve now! You can't have a downward trend with rates stable and claim Laffer!

However, I am sure you will rejoice with me in the November update forecasting a 50% rise next year in CGT receipts to $20 billion for 25-26. England is not quite finished!

https://obr.uk/efo/economic-and-fiscal-outlook-november-2025....

You’re absolutely right on the forestalling - and this is actually a perfect illustration of the Laffer curve in action.

Yes, the OBR forecasts £19.7bn for 2025-26, up from £13.7bn in 2024-25. But here’s why this supports rather than contradicts the thesis:

*That’s a one-time spike from forestalling, not sustainable revenue*

The £19.7bn is driven by people rushing to sell before the rate increases - bringing forward disposals they would have made over several years. The OBR explicitly models this as forestalling that then reverses:

- 15% lower disposals in 2025-26 (after the spike year) - 30% lower in 2026-27 - Then gradual recovery

So you get one bumper year, then years of depressed activity. The total revenue over 5 years is lower than if rates had stayed stable - classic Laffer dynamics.

*The £20bn downgrade you might have missed*

More tellingly, the OBR’s Spring Statement 2025 (March) found that CGT receipts over 2025/26-2029/30 would come in £20.6bn under the Autumn Budget forecasts made just months earlier. That’s a massive downgrade driven by “updated data on the composition of liabilities” - i.e., the behavioural responses were larger than modeled.

*Stable rates were already causing problems*

Your original point was “you can’t have a downward trend with rates stable and claim Laffer!” But that’s precisely the point - the decline from £16.9bn to £13.7bn happened before Labour’s rate increases, when rates were at 10%/20%.

What was driving it? Expectations. People knew changes were coming. Non-dom abolition was announced. Labour’s tax intentions were clear. International competition was intensifying. The behavioural response began before the policy was implemented.

*The real test*

The real question is what happens after the forestalling spike unwinds. OBR projects £25.5bn by 2029/30, but that’s based on equity prices rising with GDP and no further behavioural response. Given:

- 1,800 non-doms already left (50% above forecast) - Carried interest moving to income tax framework at 34% in April 2026 - £20bn revenue downgrade between Autumn and Spring forecasts - Continued international tax competition

…I’d wager the 2029/30 number ends up significantly below £25.5bn. We’ll know in 4-5 years, but the early indicators aren’t encouraging for the Treasury.

So yes - you’re right that forestalling creates a temporary spike. But temporary spikes that reverse aren’t evidence against the Laffer curve - they’re textbook examples of how tax policy distorts behavior and timing without increasing long-run sustainable revenue.

Can't quite remember what I was arguing for anymore...

Oh yes - well it is ofc too early to draw any conclusions yet, but my original point was... no point having a rate vastly lower than other industrialised nations - just leaves money on the table. Can never compete with zero in Dubai with low rates. Governments will have to address that in another way.

However I would say as someone who paid a chunk of tax upon selling a business, and I am way outside any actual knowledge here, CGT must be a real laggard. You generally can't just switch the domicile and the local tax man just shrugs their shoulders.