This review article presents a variety of luminescent chemosensors for the selective detection of assorted biologically relevant phosphates (phosphate ion, pyrophosphate ion and AMP, ADP and ATP) via the “Turn-On” emission mechanism. The focus has been placed to understand the design aspects, chemical structures and luminescence properties including binding constants, detection limits and lifetime parameters of the chemosensors and their emission enhancement based detection mechanism. The article concludes by addressing various future prospects both for the biological and the environmental challenges in front of the scientific community to develop intelligent chemosensors not only for detection purposes but also for remediation processes.