Reuse of treated graywater as an alternative source of water is becoming more important in view of the global water scarcity. However, various hazards and threats, particularly those pertaining to public health and the environment, impede such reuse. Technologies have been developed for treatment of wastewater with the major objective of removing specific pollutants and reduction of any perilous impact. Various photochemical and other advanced oxidation processes (AOPs) have been used for graywater treatment to mineralize the contaminants of emerging concern (CECs) in the wastewater. AOPs have exhibited remarkable potential for treatment of these pollutants at both low and high concentrations. Many of these developed technologies are capital intensive and operationally expensive. Cost-benefit analysis (CBA) combined with pricing flow analysis, environmental implications (including externalities), and social aspects of different technologies can be used as a major instrument for evaluating the sustainability of a technology. Quantifying the economics of treatment technologies would help identify technoeconomically feasible options. This chapter aims to evaluate the environmental and economic performance (ecoefficiency) and highlight the comparative cost effectiveness of various processes including photochemical and other advanced processes for graywater treatment, irrespective of their removal activities, as a sole decisive parameter. The cost of raw materials and synthesis process along with its limiting factors for the commercialization are discussed. It is expected to help in rational selection of technologies that would be affordable, environmentally sustainable, appropriate to local conditions, and acceptable to users.