Small towns face unique challenges in treating wastewater due to limited resources, expertise, and land availability. This chapter explores sustainable treatment solutions tailored to their specific needs. We introduce three main categories of suitable technologies: Natural systems (constructed wetlands, lagoons, infiltration trenches), biological treatment systems (activated sludge, anaerobic digestion), and physical–chemical treatment systems (screening, sedimentation, filtration). Each method is explained, focusing on its benefits and applicability for small towns. A comparison table highlights key factors for choosing the most suitable technology, including treatment efficiency, land requirements, operational costs, maintenance needs, and environmental impact. Additionally, the chapter showcases real-world success stories through 3 diverse case studies of small towns implementing sustainable wastewater treatment solutions. By analyzing these case studies and considering local factors, small towns can make informed decisions. The chapter concludes by offering practical recommendations for selecting the right technology and exploring future trends in sustainable wastewater treatment for small towns.