Author: [Author Name] Affiliation: [Institution] Date: April 2026 Abstract The European Union’s ambition for a frictionless single market is repeatedly challenged by cross-border tax fraud, avoidance, and administrative fragmentation. This paper introduces EuroTaxNet — a proposed decentralized yet interoperable digital framework linking the tax information systems of all EU Member States. Unlike existing mechanisms such as VAT Information Exchange System (VIES) or Tax Administration Cooperation (TAC) under Directive 2011/16/EU, EuroTaxNet leverages real-time data sharing, blockchain-based audit trails, and privacy-by-design protocols. The paper analyzes the legal, technical, and political requirements for such a system, reviews pilot projects (e.g., TADEUS, e-VAT), and proposes a phased implementation roadmap. Findings suggest that EuroTaxNet could reduce the €140 billion annual VAT gap by 25–30% while simplifying compliance for legitimate businesses.