This work presents the design and experimental validation of a dual-band fully reconfigurable circularly polarized (CP) reflectarray (RA) antenna for satellite communication applications in the Ku-band. The proposed structure operates with the downlink and uplink beams at frequency bands of [10.8-11.8] and [14-15.4] GHz, respectively. Simultaneous and independent beam control is provided over each of the two bands. The constituent unit cell is composed of two interleaved circular loops of different sizes to address the two frequency bands. Each loop is loaded using four varactor diodes. The loops are symmetrically loaded in the transverse plane to provide an isotropic response suitable for CP applications. A phase range of more than 300° is achieved in both bands as the capacitive loading varies, with an average of 2 dB loss in the lower frequency band and 3 dB loss in the higher band. In this article, the response of the unit cell is studied through full-wave simulations and verified through quasi-optical (QO) measurements, and the fully tunable performance of the reflectarray is validated through measurements in a near-field anechoic chamber.