The design of glass fiber-reinforced polymer (GFRP) reinforced concrete (RC) members is often governed by the crack width and deflection serviceability limits due to the low elastic modulus of GFRP material compared to steel. The available formulations in the current standards and guidelines control the crack widths of the GFRP-RC elements by considering the bond interaction between the GFRP reinforcement and surrounding concrete through bond-dependent coefficient, k_b. This study investigates the effect of different parameters, including the concrete compressive strength, clear concrete cover to GFRP reinforcement, and the number of GFRP reinforcement layers on the moment capacity, cracking progression, deflection behavior, and the variation of k_b values at different crack widths. The study involves experimentally testing 11 full-scale GFRP-RC beams. Moreover, a numerical parametric model was developed to investigate the effect of varying the concrete strength on the deflection performance of the GFRP-RC beams. The experimental results provided insights into how the investigated parameters impact the crack width and deflection values at the service stage. Moreover, the numerical model simulated the experimental behavior of the beams with high accuracy. It was also found that the ACI 440.1R-15 deflection formulation underestimates the deflection values at the service stage, particularly at high concrete strengths.