We present an analytical model for power transfer in a magnetoelectric-film bulk-acoustic resonator (FBAR) comprising a piezoelectric-magnetostrictive bilayer. The model describes the power flow between the elastic and magnetic systems, quantifying the transduction efficiency when the FBAR operates as a magnetic transducer. By applying the model to example systems using piezoelectric ScAlN and magnetostrictive CoFeB, Ni, or Terfenol-D layers, we demonstrate the potential for achieving high efficiencies in magnetoelectric transducers, rendering them ideal for efficient ferromagnetic resonance excitation. The validity of the model’s assumptions is confirmed through comparison with a numerical finite-element resonator model in comsol. The finite-element model further enables a comprehensive study of the resonator’s dynamic behavior, including transient and steady-state regimes, and the identification of resonant frequencies within the system.