Highlights
- Pillar Two is not a one-time filing deadline. It is an ongoing process, and the first filing season showed that rules, filing channels, and technical schemas keep changing after returns are already in motion
- Orbitax reported more than 1,700 Pillar Two filings prepared or submitted across 34 jurisdictions between November 2025 and June 2026, with about 30% of that activity occurring in the final seven days before deadlines
- Connecting ONESOURCE Tax Provision to Orbitax Global Minimum Tax lets tax departments reuse existing data mappings instead of building a parallel Pillar Two data architecture
- Embedded AI, such as Orbitax's XatBot, helps tax professionals resolve validation issues and calculation questions without leaving the filing workflow
That isn’t new. Most tax departments are already running on a patchwork of disconnected systems, with 58% reporting they’re under-resourced even before Pillar Two entered the picture.
The 2026 Corporate Tax Department Technology Report found that 64% of departments are still operating in chaotic or reactive modes. For tax teams managing a global minimum tax regime that continues to evolve across jurisdictions, that is a difficult starting point.
Pillar Two is not a single filing deadline that can be cleared and put aside. It is becoming an ongoing international tax process, requiring multinational enterprises (MNEs) to connect data, calculations, reporting, local filing requirements, review, and transmission across jurisdictions.
The challenge is therefore not simply keeping up with the rules. It is building a process that can keep working as filing requirements, validation rules, technical specifications, and deadlines change.
In broad terms, here is how to operationalize Pillar Two compliance:
- Map entity footprint and jurisdictional filing obligations across all in-scope countries
- Centralize Pillar Two data inputs from ONESOURCE Tax Provision and existing enterprise systems
- Automate GloBE calculations and safe harbor analysis through Orbitax Global Minimum Tax
- Prepare, validate, and file GIR and local returns through one connected workflow
- Standardize the process into a repeatable close runbook for each filing cycle
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The Pillar Two filing environment keeps moving
One global framework, many local obligations
Build Pillar Two compliance around the data you already have
AI guidance built into the Pillar Two workflow
Make the next Pillar Two compliance cycle easier than the first
The Pillar Two filing environment keeps moving
Pillar Two may be built around a common global framework, but the first filing season demonstrated how differently that framework is being operationalized across jurisdictions.
Tax teams had to keep pace not only with changing rules, but also with new filing channels, technical schemas, validation requirements, transmission methods, and authority-specific processes, often while the first returns were already being prepared.
In the UK, HMRC continued refining its GloBE Information Return (GIR) filing and exchange guidance throughout the season, adjusting how groups could rely on a filing made in another jurisdiction. In Australia, the ATO’s lodgment channels for the GIR and the combined global and domestic minimum tax return (CGDMTR) opened only shortly before the first deadline, with technical specifications continuing to evolve afterward. And in the Netherlands, the Digipoort and Mijn Belastingdienst Zakelijk portals did not open until June 1, 2026, only weeks before the first GIR deadline.
For multinational tax departments, these are not abstract regulatory developments. They affect whether a return can be prepared, validated, transmitted, and ultimately accepted.
When Hungary introduced a new machine-to-machine filing requirement shortly before a customer’s deadline, Orbitax adapted in time to file on schedule. That is the difference between a platform built to track rule changes and one that needs a manual update after the fact.
— Dean Matula, Solutions Consultant at Thomson Reuters
The important distinction is between knowing that a requirement has changed and being able to incorporate that change into the compliance process in time to file.
One global framework, many local obligations
The first major filing season also showed the scale of the operational challenge.
Orbitax reported that more than 1,700 Pillar Two filings were prepared or submitted across 34 jurisdictions between November 2025 and June 2026, including GIRs, notifications, QDMTT returns, top-up tax returns, registrations, self-assessment returns, and other local obligations.
Approximately 30% of the analyzed filing activity occurred during the final seven days before the relevant deadlines.
The filing count, however, tells only part of the story.
The promise of a uniform GloBE Information Return suggested that Pillar Two filing might be relatively straightforward. In practice, it became a network of registrations, notifications, top-up tax returns, and local GIR requirements that vary significantly by jurisdiction. Before a team can populate the first form, it has to understand what needs to be filed, where, and how. Our focus has been on turning that complexity into a manageable process, from tracking obligations through to populating and filing the required forms from the underlying GMT calculation.
— Jacob Fulton, Head of Quantitative Tax Practice at Orbitax
For already stretched tax departments, that complexity is difficult to scale through spreadsheets and disconnected processes.
Tax departments who tried to manage global minimum tax with manual, spreadsheet-based workflows have ended up juggling hundreds of spreadsheets, even when the up-front cost looked lower. The complexity does not disappear with a cheaper tool. It just moves further into a team’s calendar.
— Dean Matula
The opportunity for the next cycle is therefore not simply to repeat the first one. It is to turn what teams learned into a standardized and repeatable process.
Build Pillar Two compliance around the data you already have
Tax departments should not have to create a parallel data architecture for Pillar Two if the relevant information already exists across their tax and finance systems.
Connecting ONESOURCE Tax Provision to Orbitax GMT
Orbitax can connect with existing enterprise and tax data sources, including ONESOURCE Tax Provision. For organizations already using ONESOURCE, that means Pillar Two can build on existing mappings and provision data rather than starting another data collection and mapping exercise.
You already mapped your ERPs to ONESOURCE, so why not take advantage of the connection rather than undergo another mapping exercise?
— Dean Matula
The same principle applies across international tax.
Country-by-Country Reporting data can support Pillar Two transitional safe harbor calculations, while much of the same underlying data is also relevant for Public CbCR. Treating those requirements as connected processes can reduce duplication and, just as importantly, improve consistency across what a multinational calculates, files, and publicly reports.
Orbitax’s Compliance Accelerator extends that idea further by allowing existing tax data, including Form 1120 or CbC XML data, to be reused in the Pillar Two filing process.
The objective is simple: use work the tax department has already done rather than recreate it for another compliance obligation.
AI guidance built into the Pillar Two workflow
Connecting and reusing data solves only part of the problem.
Once the data moves into the Pillar Two process, tax professionals still need to understand calculations, investigate unexpected results, review filing requirements, and resolve validation issues.
The goal is to keep them moving through that work rather than sending them elsewhere to figure it out.
Automation can handle the repeatable steps, from running the GloBE calculations themselves to carrying the results into the required reporting forms. Embedded AI can help users understand what the process is producing and resolve questions without leaving the workflow.
That becomes particularly valuable at filing.
A technically correct tax position still has to pass jurisdiction-specific schemas, validation rules, and transmission requirements. When a validation fails, the tax professional should not have to stop the process, search through technical documentation, and work out what an authority’s message means.
Within Orbitax, XatBot AI can support users directly in that workflow by explaining validation issues and helping them understand how to address them in the context of the filing they are working on.
The same principle applies elsewhere in the platform. AI can help users investigate a calculation, find the relevant rule, or understand an output while remaining in the underlying tax process.
The role of AI is not to create a separate tax workflow. It is to make the existing workflow easier to execute, understand, and review.
Make the next Pillar Two compliance cycle easier than the first
The first Pillar Two filing season required tax departments to solve a new set of operational problems across data collection, calculations, safe harbors, notifications, local returns, GIRs, validation, and transmission.
Those obligations are now becoming recurring work. The next step is to make that work repeatable.
A connected approach between ONESOURCE and the Orbitax International Tax Platform allows organizations to build on data they already maintain, standardize processes across jurisdictions, and reduce the manual work required each time the cycle begins again.
Automation can handle more of the repeatable process. Embedded AI can help tax professionals navigate the questions and exceptions that arise along the way.
That is the opportunity for tax departments: not simply to keep pace with Pillar Two, but to operationalize it.
See it in action
Orbitax Global Minimum Tax connects Pillar Two calculations, compliance, filing, and transmission with the broader Orbitax International Tax Platform and ONESOURCE tax environment.
Together, ONESOURCE and Orbitax help tax departments turn Pillar Two from a collection of jurisdiction-by-jurisdiction obligations into a more connected, repeatable international tax process. That is what Pillar Two workflow automation looks like in practice: less time spent rebuilding the process, more time spent running it.
Request a free demo to see how it can fit into your existing tax workflow
