5G promises to deliver higher rates with lower latency and fixed-mobile network convergence. Passive Optical Networks (PON) have emerged as a viable option for 5G access and backhaul networks due to their cost effectiveness and high bandwidth. Improving the flexibility of network management is a key requirement of 5G, and Software Defined Networking (SDN), due to network programmability capabilities, is considered a key component of 5G. However, OpenFlow (OF), the current southbound SDN interface, has several limitations. P4 is a new language for Programming Protocol-Independent Packet Processors that promises to overcome OF’s limitations and brings in more flexibility for controlling the data plane of SDN devices. This paper presents a P4-based SDN architecture for PONs, by building a PON headend around a programmable P4 switch