The load carrying capacity of the existing bridges mostly depends on the value of traffic load. During last year’s the heavy traffic flow on the Latvian highways had considerably increased, therefore it is critical to determine the possibility of nowadays carrying traffic loads for bridges and overpasses built in different times, by using different design codes and characteristic of design loads. This paper presents simple bridge load carrying capacity rating method, based on the classification of traffic loads and load bearing capacity of bridge structures. The proposed method will assist in assessment and management of the existing bridges and ensure safe load transportation.