Design guidelines for reinforced concrete structures (RC) with fiber reinforced polymers (FRP) use the concept of partial safety factors to ensure that structural safety is attained. However, when partial safety factors are used for the design of FRP RC structures, the structural reliability levels are not known. It is very important that structural reliability targets are met, in particular when there is a change in the predominate mode of failure. Furthermore, the resistance-capacity margins between various failure modes are not known. The work reported in this paper investigates these safety-related uncertainties. The notional structural reliability levels of two FRP RC beams are evaluated for the flexural and shear failure mode. The resistance-capacity margins for these two failure modes are also evaluated. Finally, the effect of the partial safety factors on the type of the expected failure mode is investigated.