In this paper, we presented electric field calculations in the pore, and along the S4 helices, of human Na v 1.7. We demonstrated that these electric fields correlate with activity, similarly to what has been reported for enzymes in the context of electrostatic preorganization theory. More specifically, we showed that the protein residues generate non-uniform electric fields in the pore of Na v 1.7 and that areas with stronger fields coincide with minimum-energy binding sites for pore Na + . The decomposition of these fields revealed that they predominantly emanate from residues in the selectivity filter and the carboxylate outer-ring, previously identified as being critical to channel function. The electric fields exerted along the S4 helices in each domain are consistent with a sequential transition from the inactivated to closed state, where S4 in DI will move down to a resting position first, then S4 in DII and DIII, and finally S4 in DIV. Throughout this paper, the electric fields were calculated in the inactivated state of Na v 1.7, and without the application of an external potential, which suggests that ion channels are preorganized to facilitate ion binding and permeation, expanding electrostatic preorganization theory from enzymes to ion channels. Finally, we note that using electric field calculations to analyze molecular dynamics simulations offers a natural and conceptually insightful decomposition into contributions from molecular fragments in the environment without a priori assumptions about the system.