The study of inherited non-FGF23 mediated phosphaturic disorders has provided fascinating insights into the pathophysiology of calcium and phosphate homeostasis. For example, while physiologic studies of proximal tubular transport had long identified NaPiIIA as the main phosphate transporter, it was a complete surprise that the predominant clinical manifestation of loss-of-function of SLC34A1 (encoding NaPiIIA, see Table 1) was not so much hypophosphataemia, but hypercalcaemia [1]. Similarly, one of the key manifestations of loss-of-function of SLC34A3, encoding the other key phosphate transporter in the proximal tubule NaPiIIC is hypercalciuria [2]. Such clinical observations in genetically defined patients have thus revealed the close relationship between calcium and phosphate homeostasis, which reflects the dual role of the two key hormones involved: PTH, while primarily regulating blood calcium levels, also affects phosphate homeostasis. Conversely, the main phosphate-regulating hormone, FGF23, can also affect calcium levels, albeit indirectly. Here, we will first review the physiology of renal phosphate handling and then discuss specific non-FGF23 mediated phosphaturic disorders, a list of which is provided in Table 1. When accounting for the various disorders associated with renal Fanconi syndrome and Familial Hyperparathyroidism, approximately 30 different diseases are associated with phosphaturia without elevated FGF23, and a detailed discussion of all of these is beyond the scope of this review. We will therefore focus on those disorders that impair function of the renal phosphate transporters.