Double Irish and Dutch Sandwich: What Replaced Them

The Double Irish and Dutch Sandwich was, for roughly two decades, the most effective corporate tax structure ever built. It let mostly US technology and pharmaceutical groups route royalties through Ireland and the Netherlands to a zero-tax jurisdiction like Bermuda, shielding up to around USD 100 billion a year from tax before regulators shut it down (Finexity, 2024). It is now closed. No single rule replaced it.

Instead, three separate measures landed in sequence and, together, made the old structure both illegal and pointless. Ireland changed its residence rules in 2015 and let the grandfathering run out on 31 December 2020. The United States rewrote how it taxes foreign profits in 2017, then again in 2025. And the OECD pushed through a 15% global minimum tax that went live in 2024.

This article walks through how the original scheme actually moved money, then explains each of the three replacements and what they mean for anyone still thinking in terms of zero-tax conduits. The short answer: that game is over, and genuine economic substance is now the only thing that holds up.

How did the Double Irish with a Dutch Sandwich actually work?

The structure exploited a mismatch between how Ireland and the United States defined corporate tax residence, layered with a Dutch conduit to dodge withholding tax. At its peak it was described as the largest base-erosion tool in history, sheltering up to roughly USD 100 billion annually for mostly US tech and life-sciences firms (Finexity, 2024). The mechanics were elegant and entirely legal at the time.

A US parent placed its non-US intellectual property rights into a first Irish company that was managed and controlled from Bermuda. Under the old Irish rule, management from Bermuda made that company tax-resident in Bermuda, where the corporate rate was zero. A second Irish company, genuinely resident in Ireland, ran the operating business and sold products across Europe and beyond. It then paid large royalties up the chain for the right to use that IP.

Why the Dutch slice was needed

The problem was withholding tax. A direct royalty payment from the operating Irish company to the Bermuda-resident Irish company could have triggered Irish withholding tax of up to 20%. To avoid it, the groups inserted a Dutch company between the two (Finexity, 2024). Royalties flowed Ireland to the Netherlands tax-free under the EU Interest and Royalties Directive, then Netherlands to the Bermuda-resident company with no Dutch withholding tax. That tax-free middle layer is the "Dutch Sandwich."

The result: profit earned across Europe arrived in Bermuda having been taxed at close to nothing along the way. The structure relied on three jurisdictions doing exactly what their laws permitted - which is also why fixing it required changes in more than one place.

When did Ireland kill the Double Irish?

Ireland closed the structure to new entrants on 1 January 2015 through the Finance Act 2014, then let existing users continue under a five-year transition that ended on 31 December 2020 (Penn Wharton Budget Model, 2024). The reform made any company incorporated in Ireland automatically Irish tax-resident, removing the Bermuda-management loophole that made the whole structure possible.

That single change was decisive. Once an Irish-incorporated company could no longer be treated as resident in a zero-tax country merely because it was managed from there, the first Irish company in the chain lost its zero-tax home. Profits parked in it became taxable in Ireland at the standard rate. The grandfathering window simply gave multinationals time to unwind or restructure rather than face a cliff edge.

By the end of 2020, every legacy Double Irish arrangement had to be gone. Many groups responded not by leaving Ireland but by moving their IP onshore into Ireland itself, attracted by a different set of incentives the country had built to replace the old shelter.

Key takeaway: The Double Irish and Dutch Sandwich was not replaced by one new loophole. It was dismantled by Irish residence reform, US anti-deferral taxes, and a 15% global minimum tax acting together - and the new standard is real economic substance, not paper conduits.

What did Ireland replace the Double Irish with?

Ireland swapped an abusive conduit for substance-based incentives that reward IP genuinely developed and held in the country. Headline among them is the Knowledge Development Box, which offers a 10% effective corporation tax rate on qualifying IP income for accounting periods commencing before 1 January 2027, alongside capital allowances for specified intangible assets (PwC, 2025). The difference is fundamental: you must actually do the work in Ireland.

The standard Irish trading rate remains 12.5%, low by EU standards but far from zero. On top of that, capital allowances for specified intangible assets let companies write off the cost of acquired IP against the profits it generates - offsetting up to 80% of relevant IP profits, or 100% for expenditure incurred on or before 10 October 2017 (PwC, 2025). This is what pulled IP onshore after 2015.

Substance is the price of entry

The logic shifted from "where is this taxed least" to "where is this genuinely owned and developed." The Knowledge Development Box ties its 10% rate to research and development carried out in Ireland, in line with the OECD's modified nexus approach. You cannot simply license a brass-plate IP holding entity into the regime. For groups weighing European IP locations, the comparison now runs between real regimes rather than zero-tax shells - something we explore across Ireland, the Netherlands, and Luxembourg.

How does the US TCJA (GILTI and FDII) target the same behaviour?

The 2017 Tax Cuts and Jobs Act attacked offshore profit parking from the US side by taxing American multinationals on their foreign intangible income directly. It introduced GILTI, a minimum tax with a 50% Section 250 deduction that produced a 10.5% effective rate, scheduled to rise to 13.125% after 2025, plus the FDII deduction to reward IP held in the US (Tax Policy Center, 2024). Together they reduced the payoff of stashing IP in Bermuda.

GILTI - Global Intangible Low-Taxed Income - works by sweeping the lightly taxed foreign earnings of US-controlled companies into the US tax base each year, whether or not the cash comes home. That removes the deferral benefit at the heart of the old structure. FDII works as the carrot: it gives US companies a reduced rate on export income derived from US-held IP, nudging firms to keep intangibles onshore rather than offshore.

Neither rule outlaws holding IP abroad. They simply make zero-tax foreign IP far less attractive by ensuring a US-controlled group pays a meaningful minimum somewhere. For a deeper treatment of how this affects smaller owners, our blog covers GILTI mechanics in detail.

What is NCTI and how does the 2025 OBBBA change things?

From 1 January 2026, GILTI is renamed Net CFC Tested Income (NCTI) under the 2025 One Big Beautiful Bill Act, and the math gets tougher. The OBBBA repealed the QBAI deemed-10%-return exclusion and cut the Section 250 deduction from 50% to 40%, lifting the effective rate to roughly 12.6% to 14% (Bloomberg Tax, 2025). The regime survives intact; only the label and the dials have changed.

Removing the QBAI carve-out matters most. Under old GILTI, a US group could exclude a deemed 10% return on its tangible foreign assets before the minimum tax bit. That exclusion is gone, so more foreign profit falls into the net. The higher effective rate and broader base together push the US minimum on foreign earnings closer to - and in some cases above - the OECD's global floor.

Feature	GILTI (through 2025)	NCTI (from 1 Jan 2026, OBBBA)
Name	Global Intangible Low-Taxed Income	Net CFC Tested Income
Section 250 deduction	50%	40%
Effective rate	10.5% (rising to 13.125% post-2025)	~12.6% to 14%
QBAI deemed-10% return exclusion	Available	Repealed

Sources: Tax Policy Center, 2024; Bloomberg Tax, 2025.

How does the OECD Pillar Two global minimum tax finish the job?

Pillar Two installs a 15% effective minimum corporate tax rate for multinational groups with consolidated annual revenue above EUR 750 million, and it went live in 2024 (Tax Foundation, 2025). This is the measure that makes conduit structures structurally pointless. If profit ends up taxed below 15% anywhere, another country in the chain gets to "top up" the difference.

The EU phased it in through two mechanisms. The Income Inclusion Rule applied from 31 December 2023, taxing a parent on lightly taxed foreign subsidiary income. The Undertaxed Profits Rule followed from 31 December 2024, acting as a backstop that lets other jurisdictions claw back tax where the parent's country has not (Tax Foundation, 2025). Between them, there is nowhere left for low-taxed profit to hide.

The scale of the shift

This is not a niche reform. More than 130 jurisdictions agreed the two-pillar outline in October 2021, and by August 2025 around 65 countries had introduced draft or final Pillar Two legislation (Tax Foundation, 2025). The OECD estimates the minimum tax will raise global corporate income tax revenues by USD 155 to 192 billion a year, roughly 6.5% to 8.1% of global corporate tax revenue (EY, 2024).

For a structure whose entire purpose was a near-zero effective rate, a coordinated 15% floor is fatal. A Bermuda-resident IP company holding stripped profit would now simply trigger a top-up tax elsewhere in the group. The arbitrage disappears - which is precisely why the planning conversation has moved toward real substance and rate comparison, the kind you can run on our calculator.

What is the January 2026 OECD 'side-by-side' deal?

The latest twist is a US carve-out. On 5 January 2026 the OECD released a "side-by-side" package designed to address US concerns about the global minimum tax while preserving the integrity of the Pillar Two system (A&O Shearman, 2026). In broad terms, it allows the US GILTI/NCTI regime to coexist alongside Pillar Two rather than have US groups exposed to overlapping top-up taxes abroad.

The political logic is straightforward. The US already taxes its multinationals' foreign earnings through NCTI at an effective rate now approaching the global floor. Forcing those same groups through another country's top-up calculation risked double taxation and a transatlantic standoff. The side-by-side approach treats the US system as broadly equivalent for many purposes, easing the friction while keeping the 15% architecture intact for everyone else.

What it does not do is revive anything resembling the Double Irish. The accommodation is about how two minimum-tax systems interlock, not about reopening zero-tax conduits. For most groups, the practical takeaway is unchanged: budget for a real minimum tax and build genuine substance where your IP and people sit.

What does this mean for tax planning today?

Aggressive zero-tax conduit structures are dead, and the planning that replaced them is built on substance and a 15% global floor. The combination of Irish residence reform, the broadened US NCTI regime, and Pillar Two's coverage across roughly 65 legislating jurisdictions has removed the gaps the old scheme depended on (Tax Foundation, 2025). What remains is legitimate location choice, not arbitrage.

The questions worth asking now are different. Where is the IP genuinely developed and managed? Does the regime - an Irish 12.5% rate, a Knowledge Development Box, a participation exemption - reward real activity rather than paper? Will the group cross the EUR 750 million Pillar Two threshold, and if so, does its blended effective rate already clear 15%? These are the variables that drive defensible structures.

Smaller groups below the EUR 750 million threshold sit outside Pillar Two, but they still face national substance rules and anti-avoidance regimes. For anyone comparing real low-tax homes for IP or holding activity, our jurisdictions directory and comparison tool lay out the actual rates and rules side by side - including high-substance options like Cyprus and traditional zero-tax centres like Bermuda, whose role has changed sharply.

Frequently asked questions

Is the Double Irish with a Dutch Sandwich still legal?

No. Ireland closed it to new entrants from 1 January 2015 and ended the grandfathering for existing users on 31 December 2020 (Penn Wharton Budget Model, 2024). Companies incorporated in Ireland are now Irish tax-resident by default, which removes the Bermuda-management trick the structure relied on. Any legacy arrangement had to be unwound by the end of 2020.

What single thing replaced the Double Irish?

Nothing single did. Three measures combined: Ireland's 2015 residence reform plus new substance-based IP incentives, the US 2017 TCJA introducing GILTI (now NCTI from 2026), and the OECD's Pillar Two 15% global minimum tax live since 2024 (Tax Foundation, 2025). The takeaway is structural: zero-tax conduits no longer work because a minimum tax bites somewhere in the chain.

Does Pillar Two apply to small businesses?

No. Pillar Two applies only to multinational groups with consolidated annual revenue above EUR 750 million (Tax Foundation, 2025). Smaller groups fall outside the 15% global minimum tax entirely. They still face national corporate tax, substance requirements, and other anti-avoidance rules, but not the top-up mechanism that targets the largest multinationals.

Why did companies move IP into Ireland after the loophole closed?

Because Ireland replaced the shelter with genuine incentives. The Knowledge Development Box offers a 10% effective rate on qualifying IP income for periods before 1 January 2027, and capital allowances let companies write off acquired intangibles against up to 80% of relevant profits (PwC, 2025). Combined with the 12.5% trading rate, onshoring IP into Ireland became attractive on its own merits.

Disclaimer: This article is for informational purposes only and does not constitute tax, legal, or financial advice. Tax laws change frequently and vary by jurisdiction. Consult a qualified professional before acting.