IMS networks, subscriber databases, and methods are disclosed for providing AoC services in IMS networks. The subscriber database is provisioned with AoC indicators for IMS users that subscribe to AoC services. An S-CSCF in an IMS network receives a first register message from an IMS user, and transmits a second register message to the subscriber database. In response to the second register message, the subscriber database identifies an AoC indicator for the IMS user that is registering, inserts the AoC indicator in a third register message, and transmits the third register message to the S-CSCF. The S-CSCF then stores the AoC indicator for the IMS user. If a signaling message is received for a session involving the IMS user, then the S-CSCF will forward the AoC indicator for the IMS user to an AoC application server, which collects the appropriate AoC information and provides the information to the IMS user.