The effect of the reference electrode (Ag, AgClâ̂£KF + KCl or Sn, SnF₂) on the kinetics of new phase growth at interfaces formed by LaF₃:Eu²⁺ or CeF₃:Sr²⁺ single crystal solid electrolytes with metal electrodes of Ag and Bi is studied by chronoamperometry and linear scan voltammetry. It is shown that when a solid-phase reference electrode is used, the current transients reflect hindrances associated with instantaneous two- or three-dimensional nucleation as well as limitations for fluoride ion diffusion in the solid electrolyte.