Nearly 150 countries have just signed off on a global tax
deal that, in practice, gives U.S.-headquartered multinationals a significant
carve‑out from the OECD’s 15% Pillar Two global minimum tax. For U.S. groups,
this “side‑by‑side” safe harbor could mean less foreign top‑up tax exposure and
more leverage to keep planning within the U.S. system instead of around it.
The new
side‑by‑side deal
The Inclusive Framework has agreed to a “side‑by‑side
package” that adds new safe harbors on top of the existing Pillar Two rules. At
the center is a Side‑by‑Side (SbS) safe harbor and a UPE (ultimate parent
entity) safe harbor that, together, can reduce or eliminate top‑up tax in many
jurisdictions for qualifying groups.
Under the SbS model, if a multinational’s ultimate parent is
in a jurisdiction that runs its own robust minimum tax system, the group can
avoid—or dramatically limit—Pillar Two top‑up tax in other countries. Instead
of layering the OECD’s 15% minimum on top of the home country’s rules, the
package lets those two systems operate side‑by‑side,
with Pillar Two stepping back where the home regime is deemed sufficient.
How U.S.
companies won a carve‑out
In this first iteration, the United States is effectively
the sole “eligible jurisdiction” for the SbS safe harbor. The justification is
that the U.S. already has a combination of a relatively high statutory
corporate rate plus minimum‑tax‑type rules (including its own alternative
minimum mechanisms and interaction with foreign tax credits) that the deal
treats as broadly equivalent protection against base erosion.
Democratic lawmakers passed legislation in 2022 without adjusting an existing levy on offshore income, the provision for global intangible low-taxed income, to operate as a Pillar Two top-up tax. Trump then effectively withdrew from the Pillar Two tax agreement in an executive order at the start of his second term in January 2025.
The GOP's budget bill modified GILTI to get closer to Pillar Two, including by increasing its rate from 10.5% to 14%. The G7 cited these changes in its announcement that U.S. multinationals won't face Pillar Two taxes.
The practical result is that U.S.-headquartered
multinationals that meet the technical conditions and elect the safe harbor
will generally not face Pillar Two top‑up tax under the income inclusion rule
(IIR) or the undertaxed profits rule (UTPR) in other countries. Their global
effective tax outcomes are left primarily to U.S. law, rather than being
recalculated under the OECD’s 15% framework in every jurisdiction where they
operate.
The geopolitical backdrop: tax brinkmanship
This outcome did not happen in a vacuum. After the U.S.
withdrew support for the original Pillar Two implementation and signaled that
it would not enact conforming legislation, trading partners began moving ahead
with their own global minimum tax rules, raising the specter of higher foreign
tax burdens for U.S. groups. Washington responded with threats of retaliatory
“revenge taxes” and other trade/tax counter‑measures if U.S. multinationals
were targeted by overseas top‑up taxes.
The side‑by‑side compromise is, in large part, a political
off‑ramp from that stand‑off. It allows other countries to save face by keeping
Pillar Two architecture intact on paper, while carving out U.S.‑headquartered
groups through safe harbors rather than explicit exemptions written into the
model rules.
What this means for U.S. multinationals
For U.S.-based groups, the immediate attraction is clear:
·
Reduced
exposure to foreign top‑up tax under Pillar Two, especially the UTPR “backstop”
that worried many U.S. boards.
·
Less
compliance duplication from having to compute income and effective tax rates
under both U.S. rules and a full Pillar Two overlay in every jurisdiction.
At the same time, the safe harbor does not mean a free pass
from minimum taxation. Instead, it anchors U.S. multinationals more firmly in
the U.S. tax net: groups are effectively told, “If your parent is in the United
States, your minimum‑tax destiny will be decided here, not in dozens of foreign
revenue authorities.”
For tax departments and advisors, the planning focus shifts
from modeling Pillar Two top‑ups country by country to:
·
Confirming
eligibility for the U.S. safe harbor and monitoring any conditions or metrics
that could cause a group to fall out of it.
·
Re‑evaluating
structures that were built around a world with both GILTI‑style rules and a
parallel Pillar Two top‑up layer that now may never fully materialize for U.S.
parents.
Criticism
and what to watch next
Unsurprisingly, the agreement has drawn fire from
tax‑justice groups, which argue that the safe harbor undermines the original
promise of a truly global minimum tax. They warn that giving the U.S. a unique
carve‑out leaves room for profit shifting to continue through low‑tax
arrangements that sit comfortably within U.S. rules but outside the reach of
Pillar Two.
Business groups, by contrast, have largely welcomed the deal
as a pragmatic way to avoid double taxation and prevent a patchwork of punitive
“revenge” measures against U.S. companies. They view the side‑by‑side package
as a crucial stabilization of the international tax framework at a moment when
geopolitical tensions and unilateral digital taxes could easily have pushed
things in the opposite direction.
Looking ahead, the key questions for practitioners and
multinationals will be:
·
How long
the U.S. retains its status as the primary—or only—eligible jurisdiction under
the SbS safe harbor.
·
Whether
future U.S. legislative changes to minimum tax rules, or shifts in foreign
political attitudes, lead to a tightening or unwinding of the carve‑out.
For now, the message to U.S.-headquartered groups is simple:
the global minimum tax is arriving, but it will be doing so on terms that leave
the U.S. firmly in the driver’s seat.
Have an IRS Tax Problem?
Contact the Tax Lawyers at
Marini & Associates, P.A.
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