Cloud computing has revolutionized the financial sector by enabling scalable, cost-effective, and real- time transaction processing. However, the increasing volume of sensitive financial data stored and transmitted through cloud environments raises significant security concerns. Cyberattacks, unauthorized access, data breaches, and financial fraud threaten the confidentiality and integrity of transaction data. Encryption algorithms play a vital role in protecting financial information during storage and transmission. This paper examines the impact of cloud data security on financial transactions and proposes a secure framework utilizing Advanced Encryption Standard (AES), Rivest–Shamir–Adleman (RSA), and Elliptic Curve Cryptography (ECC) algorithms. The proposed architecture ensures confidentiality, integrity, authentication, and regulatory compliance while maintaining transaction efficiency. The study highlights the effectiveness of hybrid encryption approaches in securing modern cloud-based financial systems.