A method and an apparatus for completing a circuit switched service call in an Internet Protocol network are disclosed. For example, the method receives a session request from a calling party to a called party, wherein the session request includes a service tag. The method determines a value of the service tag in the session request, and queries an tElephone NUmbering Mapping (ENUM) server for one or more Naming Authority Pointer (NAPTR) resource records associated with the called party. The method selects one of the one or more NAPTR resource records in accordance with the service tag, if the one or more NAPTR resource records associated with the called party are returned, and processes the session request using the one of the one or more NAPTR resource records that is selected.