This study explores the evolving landscape of expense sharing among Saudi nationals, highlighting the significant influence of financial technology (Fintech) adoption on social and financial practices. With the rapid growth of Fintech in Saudi Arabia, mobile payment applications and peer-to-peer (P2P) money transfer platforms have emerged as pivotal tools in facilitating new forms of expense sharing among individuals, friends, and families. Through qualitative research, including semi-structured interviews with residents across Saudi Arabia, this paper explores the social dimensions of expense sharing, distinguishing between periodic and non-periodic expenses, and identifies a comprehensive five-stage process of shared financial activities. The findings indicate a generally positive attitude towards expense sharing, emphasizing benefits such as mutual aid and efficient budget management. However, challenges such as increased personal costs due to collective decisions and the complexity of managing diverse preferences also surface.