Portal Combat 2: Pillar Two compliance post-mortem

Doug McHoney (PwC’s International Tax Services Global Leader) is joined by Pat Coughlin, a Chicago-based tax director in PwC’s Quantitative Solutions and Technologies Practice within International Tax Services and a former Notre Dame running back. Doug and Pat discuss the June 30, 2026, Pillar Two compliance post-mortem, including PwC’s experience filing more than 50,000 returns with a success rate above 99%. They dive into how business rules and filing capabilities were built across dozens of jurisdictions, what late portals and conflicting validations revealed about the system, why the OECD and local tax authorities should act quickly on timely-filed GIR relief, a longer 2025 filing deadline, clearer amended-return mechanics, and broader simplification. They close with practical advice for 2025: start now, focus on calculations, and narrow review to the sections that matter most.