<![CDATA[Interfaith marriage in Indonesia continues to generate legal uncertainty because of the complex relationship between the Marriage Law, the Population Administration Law, constitutional interpretation, and judicial practice. This study examines the development of legal certainty and judicial uniformity following Constitutional Court Decision Number 24/PUU-XX/2022 and Supreme Court Circular Letter Number 2 of 2023. The research employs a normative legal method using statutory, case, conceptual, historical, and comparative approaches. Primary legal materials include the 1945 Constitution of the Republic of Indonesia, the Marriage Law, the Population Administration Law, relevant Constitutional Court decisions, and Supreme Court Circular Letter Number 2 of 2023. The findings show that Constitutional Court Decision Number 24/PUU-XX/2022 reaffirmed the constitutional position of religious law in determining marital validity, while Supreme Court Circular Letter Number 2 of 2023 strengthened consistency in judicial practice by directing judges not to grant applications for the registration of interfaith marriages. These developments have increased predictability and judicial uniformity, but they have not completely eliminated normative tensions concerning marital validity, administrative registration, judicial authority, and constitutional protection. The study therefore finds that the current legal framework has strengthened formal legal certainty, while substantive legal certainty still depends on greater coherence among statutory provisions, judicial interpretation, and administrative implementation. The study contributes to the legal discourse by distinguishing substantive legal certainty from judicial uniformity in the regulation of interfaith marriage in Indonesia.]]>
