T This final report evaluates the administrative compliance in utilizing the electroniccertificate of domicile (e-skd) and tax treaties (p3b) for article 26 withholding tax on nonresident taxpayers at pt asp (q1 2026). through a descriptive-qualitative case study utilizingobservation, interviews, and documentation, the results indicate that pt asp\\\'s e-skdadministration system aligns with withholding tax principles and minister of financeregulation (pmk) no. 112 of 2025. the application of the 20% domestic rate in the absence ofan e-skd is not a substantive violation, but rather the fulfillment of a formal withholdingresponsibility. furthermore, this final report identifies two cross-border constraints. first, astructural constraint resulting from the incompatibility of global software as a service (saas)business models with domestic regulations, which triggers gross-up burdens. second, atemporal constraint in the form of tax calendar asymmetry across jurisdictions, which ismitigated through periodic tax return (spt masa) amendments. the implications of this finalreport highlight the urgency for an anticipatory document collection strategy, the evaluation ofnet-of-tax clauses, and the need for regulators to formulate an e-skd mechanism that isadaptive to the digital economy