The sodium-dependent phosphate cotransporter (NaPi) family plays a critical role in Pi homeostasis in mammals via several mechanisms, including renal tubular reabsorption, intestinal absorption, and exchange with intracellular or bone storage. The type II NaPi transport family (SLC34) is especially important for renal and intestinal Pi handling. SLC34 protein dysfunction causes several abnormalities, such as hypophosphatemic hereditary rickets/osteomalacia and hyperphosphatemia-induced vascular disease. Expression of SLC34 family members is regulated at several steps, including transcription, translation, protein degradation, and cellular trafficking. Both hormonal (1,25-dihydroxyvitamin D3, fibroblast growth factor 23, estrogen, T3, and epidermal growth factor) and nonhormonal (dietary Pi, Ca, and vitamin A) factors regulate the transcriptional step. Here, we describe the transcriptional regulation of the SLC34 genes in the small intestine and kidney.