This chapter investigates the increasingly prevalent phenomenon of phubbing—the act of snubbing someone in a social setting by focusing on one’s phone—and its complex, bidirectional relationship with loneliness. Drawing from a wide range of interdisciplinary studies, it explores how phubbing manifests across various interpersonal contexts, including romantic relationships, friendships, parent-child dynamics, and professional environments. It highlights the detrimental psychological, emotional, and social impacts on both the phubber and the phubbee. The analysis emphasizes that while loneliness can lead to increased phubbing behaviors as a coping mechanism, phubbing in turn exacerbates feelings of isolation and dissatisfaction in relationships. Ultimately, the chapter frames phubbing as both a symptom and a cause of loneliness, perpetuating a harmful loop that hinders emotional connection and mental well-being.