The development of potassium-ion batteries (KIBs) has moved researchers one step closer to delivering batteries that promise higher cell voltage on top of advances in cost and performance as compared to their ubiquitous lithium-ion counterparts. As the key to optimizing a battery’s performance, the development of high-performance electrode materials help to increase the feasibility of KIBs technology. In this sense, phosphorus-based materials (i.e., phosphorus and metal phosphide) with high theoretical capacity and low redox potential tick all the right boxes of a material of choice. This progress report gives a rapid glimpse at recent studies on phosphorus-based anode materials for advanced KIBs, covering the synthetic methods, reaction mechanisms, electrochemical properties and performances. In addition, several promising strategies are highlighted to address the imminent challenges faced by phosphorus-based anode materials, hoping to cast an insightful outlook for possible future direction in this field.