Transitional CbCR Safe Harbour: The 3-Year Fast-Path Test

The transitional CbCR safe harbour (the TCbCR safe harbour) is the Pillar Two computation’s fast path: for the first three years of the regime, a jurisdiction whose CbCR effective tax rate is at or above 15% is excluded from the top-up tax for that year — the jurisdiction’s GloBE computation (the ACI, the covered taxes, the SBIE, the full jurisdictional ETR) not required, the CbCR data carrying the jurisdiction’s position. It is the transition measure that made the first GloBE years workable — the group’s year-one computation running on the CbCR data it already had, instead of the full GloBE computation it did not yet have — and its conditions are the group’s first-year checklist.

The test

The safe harbour’s operation, per jurisdiction, per year:

Jurisdictional CbCR ETR = (the CbCR's income tax paid + currently due)
                          ÷ the CbCR's profit (loss) before income tax

Where the CbCR ETR ≥ 15%  →  the jurisdiction is excluded from the top-up
                              tax for the year (the safe harbour applies)
Where the CbCR ETR < 15%  →  the safe harbour does not apply; the full GloBE
                              computation runs for the jurisdiction (the ACI,
                              the covered taxes, the SBIE, the jurisdictional
                              ETR, the top-up)

The CbCR ETR is the CbCR’s tax data (items 5 and 6 — the income tax paid on a cash basis and the income tax currently due on an accrual basis, over the profit before income tax — item 4) as the ratio — the same data the group files for the CbCR, used as the Pillar Two fast path. The design: the jurisdiction that looks fine on the CbCR data is, for the first three years, treated as fine — the full computation deferred, the CbCR the standard.

The scope conditions

The safe harbour applies where the conditions hold — the group-level and the jurisdiction-level:

Condition	The content
The period	The transitional safe harbour covers the first three financial years of the group’s GloBE applicability (the FY2024, FY2025 and FY2026 computations, for the groups whose first year is FY2024) — after the three years, the safe harbour expires and the full GloBE computation is the standard for every jurisdiction, every year
The CbCR used	The group uses the CbCR data (the CbCR as filed/exchanged, per the CbCR rules) as the safe harbour’s input — the CbCR the group is obligated to file (the in-scope group) is the data; a group without the CbCR obligation (the sub-threshold group — which is also out of the GloBE scope) is the non-case
The jurisdiction’s CbCR ETR ≥ 15%	The jurisdiction-level test, per year — the jurisdiction’s CbCR ETR (the tax over the profit, per the CbCR rows) at or above the 15% floor
The loss jurisdictions	The jurisdiction with the CbCR loss (the negative profit): the safe harbour’s treatment of the loss jurisdiction — the loss jurisdiction’s CbCR ETR is not computable (the negative denominator), and the model rules’ treatment applies (the loss jurisdiction’s top-up position per the GloBE rules’ loss treatment — the safe harbour does not automatically clear the loss jurisdiction; the loss’s effect on the group’s computation is per the model rules)
The specified exclusions	The model rules’ exclusions from the safe harbour’s application (the jurisdictions/entities outside the safe harbour’s scope, per the enacting jurisdiction’s implementation of the model rules)

The working reading: the safe harbour is a jurisdiction-by-jurisdiction, year-by-year clear — the group’s map runs the CbCR ETR test per jurisdiction per year, and the jurisdictions that clear are out of the computation for that year, the jurisdictions that do not clear carry the full GloBE computation. The three-year window is the transition: the first three years on the CbCR fast path, the fourth year onward on the full computation — and the group’s data discipline (the CbCR quality, the SBIE inputs, the ACI/covered-tax reconciliation) is the discipline the fourth year demands, which is why the data checklist starts in year one, not year four.

The worked fast path

A group, year one (FY2024), four jurisdictions:

Jurisdiction	CbCR profit (item 4)	CbCR tax paid + currently due (items 5+6)	CbCR ETR	Safe harbour?
J1 (the IP holding, 5%)	100	5	5.0%	No — the full GloBE computation runs (the top-up, per the worked computation)
J2 (the service centre, 25%)	300	75	25.0%	Yes — cleared, no computation, no top-up
J3 (the manufacturing base, 20%)	200	40	20.0%	Yes — cleared, no computation, no top-up
J4 (the loss jurisdiction)	(50)	0	n/c (the loss)	The loss treatment — per the model rules’ loss rules, not the safe harbour clear

The year-one computation is, in substance: the J1 GloBE computation (the top-up on the 5% holding) and the J4 loss treatment — the J2 and J3 cleared on the CbCR data, no ACI, no covered taxes, no SBIE for them, that year. The group’s year-one Pillar Two work is the J1 top-up (the IIR/UTPR/ QDMTT mechanism) and the J4 loss position — and the CbCR data is what made the J2/J3 clearance a data retrieval, not a computation.

The permanent safe harbour

Beyond the transitional safe harbour, the model rules’ permanent safe harbours operate in the steady state (from the fourth year onward, and in the transitional years where their conditions are met):

Safe harbour	The operation
The small-undertaking safe harbour	The jurisdiction’s undertakings whose profit (and revenue) are below the de minimis thresholds carry no top-up — the small jurisdiction (the small entity, the small PE) excluded from the computation, per the model rules’ thresholds
The safe harbour for specified deferred tax items	The deferred tax items (the specified temporary differences) — the transition treatment for the deferred taxes arising in the early years, per the model rules’ deferred-tax safe harbour

The permanent safe harbours are the steady-state edges — the small jurisdictions, the deferred-tax transition — and they operate alongside the full computation (the jurisdictions that do not clear a safe harbour run the full GloBE computation, the computation guide as the standard).

The group’s working position

1. Year one to three: the CbCR ETR map, per jurisdiction, per year — the fast path run on the CbCR data, the clearing jurisdictions out of the computation, the non-clearing jurisdictions into the full GloBE computation. The map is the Pillar Two for TP teams working document, year by year.
2. The CbCR data quality is the safe harbour’s defence — the CbCR ETR is the CbCR’s tax and profit data, and the data that does not reconcile to the filings is the ETR the authority recomputes — the CbCR data quality discipline is the safe harbour’s precondition.
3. Year four: the full computation, every jurisdiction — the transitional safe harbour expires; the ACI, the covered taxes, the SBIE, the jurisdictional ETR, per jurisdiction, per year — the data discipline (the payroll, the assets, the tax filings’ reconciliation) that the transitional years should have been building, is the steady state’s requirement.
4. The loss jurisdictions, every year — the loss treatment is the model rules’ computation, not the safe harbour’s clear — the loss jurisdiction’s position, year by year, per the GloBE rules’ loss treatment.

See also

• Pillar Two explained
• GloBE rules — the full computation
• ETR and SBIE
• CbCR and Pillar Two — the data backbone