Planned Obsolescence is a threat to sustainability and is a practice that has increased in recent years. Manufacturers and companies are often blamed, but recent research has shown that consumers play a significant role and thus hold considerable responsibility for Planned Obsolescence practices. This thesis explores the effect that Planned Obsolescence in smartphones has on sustainable consumers who reside in Sweden. Focus groups and individual interviews were carried out with sixteen participants who were identified as sustainable consumers. The results were diverse and related to different situational, social, and psychological aspects classified into four categories: social elements, implied premature upgrading, psychological elements, and misalignment in sustainable values and behaviour. The study concludes that Planned Obsolescence in smartphones creates a social barrier that does not allow sustainable consumers to maintain their sustainable consuming habits within this sector and provokes negative feelings within them, which interlink with social circumstances. Moreover, this phenomenon affects consumers by implying that they constantly should replace their devices even though they are rather satisfied with their current ones. Finally, Planned Obsolescence in smartphones broadens the gap between consumers’ sustainable values and behaviours, and this inconsistency seems to be more significant for smartphones than in other sectors.