A system is provided for mobile client-side location determination. The system includes a mobile device, which includes base transceiver station location data, a memory, a processor, and a location engine stored in the memory. When executed by the processor, the location engine receives information that identifies multiple base transceiver stations in response to the mobile device registering with a communication network. The location engine also reads a location for each of the base transceiver stations from the base transceiver station location data and calculates a location of the mobile device based on the location of each of the base transceiver stations. Additionally, the location engine provides the location of the mobile device in a defined portion of a communication transmitted by the mobile device.