A method for preventing overload conditions in a communication system. The communication system performs a call load analysis and admits a subscriber requesting admission (or responding to a page) to the system based on the result of the call load analysis. The call load analysis is based on the signal to noise power ratios of all subscribers already admitted to the communication system. External jammer signals that interfere with subscriber signals thus reducing the coverage of the communication system do not affect the call load analysis. The jammer signals therefore, do not hinder an efficient use of the capacity of the communication system. A threshold value is established and such threshold value is compared to an average call load value calculated from a plurality of instantaneous call load values. When the calculated average call load value is substantially equal to or above the established threshold, no subscribers are admitted to the communication system; subscribers are admitted when the calculated average call load value is below the established threshold. Individual subscribers whose contributions to the average call load value are deemed significant (tending to cause or actually causing overload conditions) are identified and removed from the system.