Track Access Charge Harmonisation for Cross-Border Rail Services

National track access charge (TAC) regimes create persistent pricing inconsistency that undermines cross-border rail competitiveness, a challenge acute along Rail Baltica (RB) – the developing corridor spanning Estonia, Latvia, and Lithuania. This study examines under what conditions TAC harmonisation is achievable along this corridor and what framework would best support phased alignment. A comparative case analysis of the three Baltic states is conducted using regulatory filings, EU policy documentation, and infrastructure manager data, with descriptive analysis mapping structural divergences across national TAC regimes. The analysis identifies quantifiable differences in charging structures and delineates metrics where harmonisation is already viable. A forward agenda specifies the regulatory and governance preconditions required for deeper alignment. The findings confirm that full TAC unification remains premature, constrained primarily by divergent interpretations of the common EU legal framework and deeply embedded national accounting methodologies, while structured harmonisation through a shared methodological framework can meaningfully improve pricing transparency and regulatory comparability without undermining national financial autonomy. The decision-support framework developed here offers a transferable instrument for infrastructure managers, regulators, and EU-level bodies pursuing TAC reform across cross-border corridors.