Methods and systems provide dynamic determination of a control-channel bit rate. An access node provides service on a carrier comprising active and idle timeslots, active timeslots comprising a data channel for carrying a control channel at a bit rate that can be set to a lower value or a higher value, and traffic channels. The access node determines whether the number of active timeslots over a time period is less than a first threshold. If so, the access node sets the bit rate to the lower value. If not, the access node sets the bit rate to the higher value if at least one of the following is true: (a) control-channel occupancy exceeds a second threshold, (b) the amount of data in a traffic buffer exceeds a third threshold, and (c) control-channel occupancy exceeds a fourth threshold and the amount of data in the traffic buffer exceeds a fifth threshold.