Superhydrophobic surfaces have been fabricated on flexible fluorinated ethylene propylene (FEP) foils using nanoimprint lithography (NIL) and roughening by plasma etching. The combination of these two techniques results in hierarchical structures and superhydrophobic properties. The icephobic behavior of the surfaces has been studied with measurements of the freezing delay time (FDT) of water droplets on cooled surfaces. It is demonstrated in this paper that the variability of the FDT values is due to the electrostatic surface potential Vs. The impact of this parameter is explored and it is shown that the delay of freezing increases when the surface potential decreases from 0 to −500 V, and decreases for lower surface potentials. This decrease is related to the saturation effect of contact angle, which is well known in electrowetting literature. Contact angles analysis confirms that this saturation effect occurs around −500 V in the present experimental case. The effect of potential surface polarity is also discussed. By optimizing surface potentials of FEP hierarchical structures, it is possible to obtain FDT higher than 40 min at −15 °C.