The first major global filing season for Pillar Two has provided an early view of what it takes to administer the new global minimum tax regime in practice, according to international tax platform Orbitax.
The company analyzed more than 1,700 Pillar Two filings prepared or submitted through its international tax platform across 34 jurisdictions between Nov. 1, 2025, and June 30, 2026.
The data from the first major global filing season shows that compliance extended far beyond the GloBE Information Return: GIR notifications and self-assessment returns represented more than 60% of filing activity, while approximately 30 percent of analyzed filings were created during the final week before June 30.
“Together, the findings provide an early operational view of how the new 15% global minimum tax regime is affecting multinational tax departments as they move from policy interpretation, modeling, and data readiness into recurring multi-jurisdiction compliance,” Orbitax said.
What the first filing season revealed
The filing data shows that Pillar Two compliance extends far beyond the GloBE Information Return.
GIR notifications and self-assessment returns represented more than 60% of recorded filing activity through the Orbitax platform. Registrations, Qualified Domestic Minimum Top-up Tax returns, Income Inclusion Rule returns, and GIRs added hundreds of further obligations.
For multinational groups, this created a broader operational challenge. Tax teams had to identify applicable requirements across their global footprint, coordinate multiple forms from a common data set, meet different local deadlines, apply jurisdiction-specific validation rules, and navigate newly introduced authority systems.
The first filing season also showed how sharply global compliance activity can accelerate as a common deadline approaches.
Of the platform filings included in the timing analysis, approximately 30% were created during the final seven days before June 30. In several jurisdictions, including Canada, the United Kingdom, Switzerland, Germany, the Netherlands, Sweden, and Austria, approximately one-third or more of analyzed filing activity occurred during the final week.
The surge was not driven by GIRs alone, according to Orbitax. GIR notifications and self-assessment returns represented almost two-thirds of the identified filing types created during those seven days.
The pattern reflects the dependencies involved in multinational compliance. Calculations may be substantially complete before the deadline, but submissions can remain dependent on final data reviews, internal approvals, local interpretations, and validation results.
“My main suggestion is to start well before the deadline, and to actually understand what you’re facing,” Laszlo Icsu, senior director, head of tax Europe, APAC and CEE at EPAM Systems, said in a statement. “I started on the data and the top-up tax calculations about a year and a half before the filing itself, and that gave us enough lead time.”
EPAM managed financial year 2024 Pillar Two filings across 27 countries, including GIRs, QDMTT returns, zero-liability returns, and notifications.
The practical lesson from the first season is that Pillar Two compliance must be designed for periods of peak activity, Orbitax says. Tax teams need sufficient structure, visibility, and processing capacity to maintain control as multiple filings, reviews, and authority interactions converge.
Canada and the U.K. together accounted for approximately 38% of recorded filing activity. The five highest-volume jurisdictions represented a little more than half of the total, while nearly one-third of activity fell outside the 10 highest-volume jurisdictions.
That distribution highlights the long tail of local requirements. Even jurisdictions with relatively limited filing volume require local analysis, form support, validation rules, deadline tracking, and an appropriate submission process, Orbitax says.
Lessons for the next cycle
Behind each filing was a tax team working through evolving local requirements, data questions, internal reviews, validation errors, and submission procedures.
The season required close coordination among multinational tax departments, advisory firms, tax specialists, implementation teams, developers, support professionals, and tax authorities.
“The volume is important, but the larger story is the coordination behind it,” Bianca Kuijper, chief operating officer at Orbitax, said in a statement. “Customers, partners, tax experts, developers, and support teams worked across jurisdictions and time zones to resolve issues as they emerged and keep filings moving. Every validation question, authority response, and successful submission created practical knowledge that can improve the process for the next filer.”
The June 30 deadline closed the first major filing cycle, but the work continues. Tax teams are now managing authority feedback, corrections, amended returns, and resubmissions while preparing for jurisdictions whose first major Pillar Two deadlines will fall in the next cycle, Orbitax says.
“The first season showed that Pillar Two compliance requires more than technical tax knowledge. It also requires coordinated workflows, clear ownership, sufficient processing capacity, and technology that can support execution across jurisdictions,” the company added
Photo credit: jcomp/Freepik
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Tags: compliance, international tax, Pillar Two, tax compliance, Taxes
