‌Context & Objective: The commitment to banking confidentiality is a fundamental principle within the global banking industry, emphasizing the duty of banks, acting in a fiduciary capacity, to protect the financial and identity-related privacy of their clients. As drivers of economic growth and capital attraction, financial institutions must prioritize secrecy. However, modern banking ecosystems introduce significant challenges to maintaining this privacy. In jurisdictions such as Switzerland, this duty is reflected in strict legislative frameworks where even inadvertent breaches are subject to criminal sanctions. Conversely, the Iranian legal system lacks a specific, unified statute governing confidentiality and its corresponding enforcement guarantees, relying instead on scattered legal foundations. The multiplicity of state entities authorized to access client information and a lack of transparency regarding jurisdictions have historically marginalized banking secrecy in Iran. This study investigates the legal foundations, sources, and multifaceted challenges of maintaining banking secrecy through a comparative legal analysis of the Iranian and Swiss jurisdictions.
 ‌Method & Approach: The research employs a doctrinal legal methodology to analyze the statutory texts, regulatory frameworks, and legal principles governing banking confidentiality in both jurisdictions. To supplement the doctrinal analysis and consolidate practical insights, the study utilizes structured interviews to gather the perspectives of twenty recognized subject-matter experts. This panel consists exclusively of current and former senior executives from the Central Bank of the Islamic Republic of Iran, the Iranian National Tax Administration, the General Inspection Office, the Supreme Audit Court, the broader banking network, and the Financial Intelligence Unit.
 ‌Findings: The comparative analysis reveals stark contrasts in legislative architectures. Switzerland maintains a robust legal regime rooted in its Civil Code, Penal Code, and Article 47 of the Federal Banking Act, which explicitly criminalizes breaches of banking secrecy. In contrast, Iranian jurisprudence relies on fragmented provisions, including Article 25 of the Constitution, Article 648 of the Islamic Penal Code, the Electronic Commerce Law, and the Central Bank Law. None of these provide a comprehensive framework defining banking secrecy, its scope, or precise penalties for its breach. The study identifies several primary challenges, notably the inherent conflict between individual privacy and state supervision. Additional challenges include insufficient enforcement mechanisms for unauthorized disclosures in Iran, the pressure of international sanctions and reporting obligations to international bodies, and the tension between attracting capital and meeting transparency requirements. Furthermore, systemic vulnerabilities in Iran often result in unauthorized data exposure during legally mandated disclosure procedures, risking a severe loss of public trust and subsequent economic instability. Iranian experts unanimously confirmed the inadequacy of current domestic laws, highlighting the absence of specialized criminalization.
 ‌Conclusion: While absolute banking secrecy is globally shifting toward greater transparency to combat financial crimes, limitations on this duty must strictly align with public interest without disproportionately compromising privacy. Switzerland successfully balances these competing interests, retaining its status as a global financial center by strictly limiting disclosures to specified legal and judicial exceptions. Conversely, the lack of a dedicated legal framework in Iran leads to inconsistent enforcement and arbitrary privacy breaches, facilitating capital flight and broader economic damage. To mitigate these risks, the Iranian legislature must draft and enact a comprehensive, unified statute defining the exact parameters, authorized access levels, and stringent penalties regarding banking secrecy. In the interim, incorporating explicit non-disclosure clauses into standard banking contracts is recommended as a practical safeguard against unauthorized disclosures.