When Pillar Two regulations emerged, the complexity was daunting. For many organisations, outsourcing felt prudent – let the experts handle it whilst we focus on our core business. But Pillar Two compliance is not a back-office checkbox you can hand off without consequence. Outsourcing the mechanics of Pillar Two may look attractive: reduced headcount, access to tax specialists, faster initial delivery.
However, it also creates blind spots and governance gaps. Consider the parallels with traditional corporate tax compliance. Few large groups outsource their year-end reporting long-term because they need control, visibility, and the ability to meet their own reporting timelines.
When Outsourcing Stops Being the Safe Option
The rules were complex, timelines tight, and few in-house teams had the capacity to interpret the framework while redesigning internal processes. Initially, outsourcing felt logical for many. But organisations are discovering that outsourcing hasn’t removed their challenges; it has simply relocated them beyond their line of sight. The hidden costs of outsourcing:
- Fragmented coverage: Many providers still lack global QDMTT readiness or offer it in disconnected modules. When regulations evolve, or your business changes, your compliance capability stalls until your provider catches up.
- Disconnected calculations: GloBE and local QDMTT computations often run in parallel silos, resulting in reconciliation gaps, mismatched assumptions, and difficulty establishing confidence in the final numbers.
- ‘Black box’ methodologies: Without visibility into methodology, data transformations, or modelling logic, tax teams struggle to explain positions to auditors, respond to board questions, or integrate Pillar Two outputs into broader tax reporting and strategy.
- Timeline misalignment: Outsourced processes work to the provider’s schedule, potentially delaying your financial close and undermining the efficiency you sought.
- Vendor dependency: Proprietary integrations and modelling frameworks make transitions difficult. Over time, institutional knowledge shifts outside the organisation, increasing reliance and raising the long-term cost of change.
The Custom Build Conundrum
Whilst some organisations outsourced, others built custom Pillar Two solutions within their existing ERP systems. Often, these were positioned as strategic long-term investments offering a tailored in-house solution. Many of these expensive, bespoke builds are already struggling to adapt to evolving rules and requiring significant reinvestment just to reach basic compliance.
The fundamental problem is that Pillar Two is not a static ruleset. It continues to evolve across jurisdictions with additional guidance and local legislation. Custom solutions lack the ability to respond quickly. Every change becomes an IT project.
Why Keep Pillar Two In-House?
Forward‑thinking tax leaders are keeping Pillar Two under their control. Not because they want more work, but because they recognise that Pillar Two is fundamentally a data challenge, not a one‑off advisory exercise. Keeping the core of Pillar Two in‑house delivers critical advantages:
- Strategic alignment: Pillar Two affects tax policy, structuring, forecast models, and long-term planning. Maintaining core capabilities ensures control over elections, assumptions, and methodologies, ensuring these are all aligned with broader corporate strategy.
- End‑to‑end transparency: An in-house function can access raw data, run sensitivity analyses and trace outputs back to source. This improves confidence in reported figures, shortens query cycles with auditors and enables faster, more confident decision-making.
- Stronger governance: Retaining ownership allows for clear accountability, consistent application of policy choices, and more robust internal controls.
- Agile response to regulatory change: In-house teams can update methodologies as regulations evolve. They can prioritise updates based on business impact and ensure documentation, reporting and stakeholder communications are coordinated.
- Retention of knowledge: Pillar Two will is here to stay and will shape tax policy and process for years. Building and retaining expertise internally means capability grows with each compliance cycle and reduces the long-term costs of dependency.
The Middle Ground
Bringing Pillar Two in-house doesn’t have to mean going it alone. Many organisations are adopting a co-sourcing model, leveraging technology to handle the heavy lifting of data, calculations, workflow and documentation; whilst advisors provide targeted technical interpretation and jurisdictional insight where needed.
This approach provides the control and efficiency of an in-house model with the confidence of expert review where you need it most. Technology excels at data management, calculation, and process automation, whilst advisors support addresses complex interpretations, which is particularly valuable in the early years of compliance.
Time to Reassess
Pillar Two isn’t going away. Organisations are now facing the full end-to-end realities of compliance, and many are discovering significant gaps in their current approach. If you’re in an outsourcing arrangement that isn’t delivering the control, transparency, or efficiency you expected, you’re not alone, and you’re not stuck.
Before your next compliance cycle begins, ask yourself: Are you genuinely satisfied with your current model?
Take Action
If you’re questioning whether your Pillar Two strategy is sustainable, Praesto Consulting can help. We help multinational groups build compliant, efficient, and future‑proof Pillar Two operating models. Whether you want to optimise your current model, transition to an in-house approach, or implement a strategic co-sourcing framework, we can help.
Contact us today to discuss how your organisation can build a Pillar Two compliance model that works for you. In an environment of evolving regulations and increasing scrutiny, control over your tax data and processes isn’t just preferable, it’s essential.