Example modular optical network terminals (ONTs) and methods to implement the same are disclosed. A disclosed example ONT includes a base unit having an integral optical interface to optically couple the ONT to an optical network, and to convert an optical signal received from the optical network to form an electrical signal, a plug-in service module to distribute the electrical signal within a customer premises, and a modular interface connector configured to receive the plug-in service module and to couple the electrical signal from the base unit to the plug-in service module.