New rat-race couplers that can be operated at two separate frequency bands are presented. The design is accomplished by transforming the lengths and impedances of the conventional rat-race into dual band T or П shaped sections. Simple design equations are used for basic design geometries. Then the rat-race coupler geometries are analyzed using a full wave electromagnetic (EM) simulator and then realized at 0.9425 and 1.96 GHz for global system of mobile communications (GSM) bands. Excellent agreement between simulated and measured results demonstrates the performance of the proposed couplers. Both ring structures have a wide frequency operation range in addition to the significant reduced-size of the П-section based coupler. Index Terms- Ra